feat: display friendly names for memory files (closes #177)

The memory file list now shows human-readable titles instead of raw
filenames wherever possible.

- Rust: adds `MemoryFileInfo { path, heading }` and updates
  `MemoryFilesResponse` to use `Vec<MemoryFileInfo>`; adds
  `extract_first_heading()` helper that scans the first `# Heading`
  from a file's content; both `list_memory_files_native` and
  `list_memory_files_via_wsl` now read each file and populate the
  heading field; raw filename remains available as a fallback
- Frontend: updates `MemoryBrowserPanel.svelte` to use the richer type;
  adds `getDisplayName()` which returns the heading or falls back to the
  raw filename; file buttons use the display name with the raw filename
  as a tooltip; the viewer header also shows the display name with the
  filename shown as a subtitle when a heading is present
- Tests: 8 new Rust unit tests for `extract_first_heading` (happy path,
  edge cases, empty content, whitespace); 12 new TypeScript tests for
  `getFileName` and `getDisplayName` mirrored from the component

src-tauri/src/commands.rs

@@ -862,6 +862,26 @@ pub async fn read_file_content(path: String) -> Result<String, String> {
         .map_err(|e| format!("Failed to read file: {}", e))
 }
 
+/// Read the first `# Heading` from a WSL file path (for Windows).
+/// Returns `None` if the file cannot be read or has no top-level heading.
+#[cfg(target_os = "windows")]
+fn read_wsl_file_first_heading(path: &str) -> Option<String> {
+    use std::process::Command;
+
+    let output = Command::new("wsl")
+        .hide_window()
+        .args(["-e", "bash", "-c", &format!("head -20 '{}'", path)])
+        .output()
+        .ok()?;
+
+    if !output.status.success() {
+        return None;
+    }
+
+    let content = String::from_utf8_lossy(&output.stdout);
+    extract_first_heading(&content)
+}
+
 /// Read file content via WSL (for Windows with WSL paths)
 #[allow(dead_code)]
 async fn read_file_via_wsl(path: &str) -> Result<String, String> {
@@ -1353,9 +1373,29 @@ pub async fn close_application(app_handle: AppHandle) -> Result<(), String> {
     Ok(())
 }
 
+#[derive(serde::Serialize)]
+pub struct MemoryFileInfo {
+    pub path: String,
+    pub heading: Option<String>,
+}
+
 #[derive(serde::Serialize)]
 pub struct MemoryFilesResponse {
-    pub files: Vec<String>,
+    pub files: Vec<MemoryFileInfo>,
+}
+
+/// Extract the first `# Heading` from a string of file content.
+fn extract_first_heading(content: &str) -> Option<String> {
+    content.lines().find_map(|line| {
+        let trimmed = line.trim();
+        if let Some(rest) = trimmed.strip_prefix("# ") {
+            let heading = rest.trim().to_string();
+            if !heading.is_empty() {
+                return Some(heading);
+            }
+        }
+        None
+    })
 }
 
 #[tauri::command]
@@ -1398,12 +1438,19 @@ async fn list_memory_files_via_wsl() -> Result<MemoryFilesResponse, String> {
     }
 
     let stdout = String::from_utf8_lossy(&output.stdout);
-    let files: Vec<String> = stdout
+    let paths: Vec<String> = stdout
         .lines()
         .filter(|line| !line.trim().is_empty())
         .map(|line| line.trim().to_string())
         .collect();
 
+    // Read first heading from each file via WSL
+    let mut files = Vec::new();
+    for path in paths {
+        let heading = read_wsl_file_first_heading(&path);
+        files.push(MemoryFileInfo { path, heading });
+    }
+
     Ok(MemoryFilesResponse { files })
 }
 
@@ -1425,10 +1472,13 @@ async fn list_memory_files_native() -> Result<MemoryFilesResponse, String> {
         return Ok(MemoryFilesResponse { files: Vec::new() });
     }
 
-    let mut memory_files = Vec::new();
+    let mut memory_paths = Vec::new();
 
     // Recursively find all memory directories
-    fn find_memory_files(dir: &std::path::Path, files: &mut Vec<String>) -> std::io::Result<()> {
+    fn find_memory_files(
+        dir: &std::path::Path,
+        files: &mut Vec<String>,
+    ) -> std::io::Result<()> {
         if !dir.is_dir() {
             return Ok(());
         }
@@ -1461,16 +1511,25 @@ async fn list_memory_files_native() -> Result<MemoryFilesResponse, String> {
         Ok(())
     }
 
-    if let Err(e) = find_memory_files(&projects_dir, &mut memory_files) {
+    if let Err(e) = find_memory_files(&projects_dir, &mut memory_paths) {
         return Err(format!("Failed to list memory files: {}", e));
     }
 
     // Sort files alphabetically
-    memory_files.sort();
+    memory_paths.sort();
 
-    Ok(MemoryFilesResponse {
-        files: memory_files,
-    })
+    // Read first heading from each file
+    let files = memory_paths
+        .into_iter()
+        .map(|path| {
+            let heading = fs::read_to_string(&path)
+                .ok()
+                .and_then(|content| extract_first_heading(&content));
+            MemoryFileInfo { path, heading }
+        })
+        .collect();
+
+    Ok(MemoryFilesResponse { files })
 }
 
 #[tauri::command]
@@ -2902,4 +2961,65 @@ gitea: gitea-mcp -t stdio (STDIO) - ✓ Connected"#;
         assert_eq!(servers[0].name, "asana");
         assert_eq!(servers[1].name, "gitea");
     }
+
+    // ==================== extract_first_heading tests ====================
+
+    #[test]
+    fn test_extract_first_heading_returns_heading() {
+        let content = "# My Memory File\n\nSome content here.";
+        assert_eq!(
+            extract_first_heading(content),
+            Some("My Memory File".to_string())
+        );
+    }
+
+    #[test]
+    fn test_extract_first_heading_ignores_non_h1() {
+        let content = "## Section Header\n### Sub-section\nSome content.";
+        assert_eq!(extract_first_heading(content), None);
+    }
+
+    #[test]
+    fn test_extract_first_heading_finds_first_h1_after_other_lines() {
+        let content = "Some intro text\n\n# The Real Title\n\nMore content.";
+        assert_eq!(
+            extract_first_heading(content),
+            Some("The Real Title".to_string())
+        );
+    }
+
+    #[test]
+    fn test_extract_first_heading_trims_whitespace() {
+        let content = "#   Trimmed Heading   \n\nContent.";
+        assert_eq!(
+            extract_first_heading(content),
+            Some("Trimmed Heading".to_string())
+        );
+    }
+
+    #[test]
+    fn test_extract_first_heading_returns_none_for_empty_content() {
+        assert_eq!(extract_first_heading(""), None);
+    }
+
+    #[test]
+    fn test_extract_first_heading_returns_none_for_empty_heading() {
+        let content = "# \n\nContent after empty heading.";
+        assert_eq!(extract_first_heading(content), None);
+    }
+
+    #[test]
+    fn test_extract_first_heading_returns_none_when_no_headings() {
+        let content = "Just some plain text.\nNo headings here at all.";
+        assert_eq!(extract_first_heading(content), None);
+    }
+
+    #[test]
+    fn test_extract_first_heading_handles_leading_whitespace_on_line() {
+        let content = "   # Indented Heading\n\nContent.";
+        assert_eq!(
+            extract_first_heading(content),
+            Some("Indented Heading".to_string())
+        );
+    }
 }

src/lib/components/MemoryBrowserPanel.svelte

@@ -3,17 +3,22 @@
   import { invoke } from "@tauri-apps/api/core";
   import Markdown from "./Markdown.svelte";
 
-  let memoryFiles: string[] = $state([]);
+  interface MemoryFileInfo {
+    path: string;
+    heading: string | null;
+  }
+
+  interface MemoryFilesResponse {
+    files: MemoryFileInfo[];
+  }
+
+  let memoryFiles: MemoryFileInfo[] = $state([]);
   let selectedFile: string | null = $state(null);
   let fileContent: string = $state("");
   let isLoading = $state(false);
   let error: string | null = $state(null);
   let isPanelOpen = $state(false);
 
-  interface MemoryFilesResponse {
-    files: string[];
-  }
-
   async function loadMemoryFiles() {
     isLoading = true;
     error = null;
@@ -49,6 +54,10 @@
     return path.split("/").pop() || path;
   }
 
+  function getDisplayName(file: MemoryFileInfo): string {
+    return file.heading ?? getFileName(file.path);
+  }
+
   function togglePanel() {
     isPanelOpen = !isPanelOpen;
     if (isPanelOpen && memoryFiles.length === 0) {
@@ -151,11 +160,12 @@
       {:else}
         <div class="panel-layout">
           <div class="file-list">
-            {#each memoryFiles as file (file)}
+            {#each memoryFiles as file (file.path)}
               <button
                 class="file-item"
-                class:active={selectedFile === file}
-                onclick={() => loadFileContent(file)}
+                class:active={selectedFile === file.path}
+                onclick={() => loadFileContent(file.path)}
+                title={getFileName(file.path)}
               >
                 <svg
                   class="file-icon"
@@ -171,7 +181,7 @@
                     d="M9 12h6m-6 4h6m2 5H7a2 2 0 01-2-2V5a2 2 0 012-2h5.586a1 1 0 01.707.293l5.414 5.414a1 1 0 01.293.707V19a2 2 0 01-2 2z"
                   />
                 </svg>
-                <span class="file-name">{getFileName(file)}</span>
+                <span class="file-name">{getDisplayName(file)}</span>
               </button>
             {/each}
           </div>
@@ -179,7 +189,12 @@
           <div class="file-viewer">
             {#if selectedFile && fileContent}
               <div class="viewer-header">
-                <h4>{getFileName(selectedFile)}</h4>
+                {#each memoryFiles.filter((f) => f.path === selectedFile) as activeFile (activeFile.path)}
+                  <h4>{getDisplayName(activeFile)}</h4>
+                  {#if activeFile.heading}
+                    <p class="viewer-filename">{getFileName(activeFile.path)}</p>
+                  {/if}
+                {/each}
               </div>
               <div class="viewer-content">
                 <Markdown content={fileContent} />
@@ -438,6 +453,13 @@
     color: var(--text-primary);
   }
 
+  .viewer-filename {
+    margin: 0.25rem 0 0;
+    font-size: 0.75rem;
+    color: var(--text-tertiary);
+    font-family: monospace;
+  }
+
   .viewer-content {
     flex: 1;
     padding: 1.5rem;

src/lib/components/MemoryBrowserPanel.test.ts

@@ -0,0 +1,98 @@
+import { describe, it, expect } from "vitest";
+
+// Mirror pure logic functions from MemoryBrowserPanel.svelte
+
+interface MemoryFileInfo {
+  path: string;
+  heading: string | null;
+}
+
+function getFileName(path: string): string {
+  return path.split("/").pop() || path;
+}
+
+function getDisplayName(file: MemoryFileInfo): string {
+  return file.heading ?? getFileName(file.path);
+}
+
+describe("getFileName", () => {
+  it("extracts the filename from an absolute Unix path", () => {
+    expect(getFileName("/home/naomi/.claude/projects/foo/memory/MEMORY.md")).toBe("MEMORY.md");
+  });
+
+  it("extracts the filename from a nested path", () => {
+    expect(getFileName("/home/naomi/.claude/projects/foo/memory/debugging.md")).toBe(
+      "debugging.md"
+    );
+  });
+
+  it("returns the path itself when there is no slash", () => {
+    expect(getFileName("MEMORY.md")).toBe("MEMORY.md");
+  });
+
+  it("returns the path when the path ends with a slash (empty filename)", () => {
+    // split('/').pop() returns '' for trailing slash → falls back to full path
+    expect(getFileName("/some/dir/")).toBe("/some/dir/");
+  });
+
+  it("handles single-component paths", () => {
+    expect(getFileName("notes.md")).toBe("notes.md");
+  });
+
+  it("handles Windows-style paths passed as Unix strings", () => {
+    // If the path contains no forward slashes, the whole string is the filename
+    expect(getFileName("C:\\Users\\naomi\\memory\\file.md")).toBe(
+      "C:\\Users\\naomi\\memory\\file.md"
+    );
+  });
+});
+
+describe("getDisplayName", () => {
+  it("returns the heading when the file has one", () => {
+    const file: MemoryFileInfo = {
+      path: "/home/naomi/.claude/projects/foo/memory/MEMORY.md",
+      heading: "Hikari Desktop - Memory",
+    };
+    expect(getDisplayName(file)).toBe("Hikari Desktop - Memory");
+  });
+
+  it("falls back to the filename when heading is null", () => {
+    const file: MemoryFileInfo = {
+      path: "/home/naomi/.claude/projects/foo/memory/debugging.md",
+      heading: null,
+    };
+    expect(getDisplayName(file)).toBe("debugging.md");
+  });
+
+  it("falls back to the filename when heading is an empty string stored as null", () => {
+    const file: MemoryFileInfo = {
+      path: "/home/naomi/.claude/projects/foo/memory/patterns.md",
+      heading: null,
+    };
+    expect(getDisplayName(file)).toBe("patterns.md");
+  });
+
+  it("returns the heading even when it matches the filename", () => {
+    const file: MemoryFileInfo = {
+      path: "/home/naomi/.claude/projects/foo/memory/MEMORY.md",
+      heading: "MEMORY",
+    };
+    expect(getDisplayName(file)).toBe("MEMORY");
+  });
+
+  it("returns a multi-word heading verbatim", () => {
+    const file: MemoryFileInfo = {
+      path: "/some/path/foo.md",
+      heading: "My Detailed Debugging Notes",
+    };
+    expect(getDisplayName(file)).toBe("My Detailed Debugging Notes");
+  });
+
+  it("falls back gracefully when path has no directory separators", () => {
+    const file: MemoryFileInfo = {
+      path: "lonely-file.md",
+      heading: null,
+    };
+    expect(getDisplayName(file)).toBe("lonely-file.md");
+  });
+});