feat: add compact mode for minimal widget interface (#36)

Add a compact mode that shrinks the window to a small widget showing
just the character sprite, recent messages, and a quick input box.
Perfect for quick questions while working without the full UI.

- Add CompactMode.svelte component with minimal widget interface
- Add compact mode toggle in StatusBar (Ctrl+Shift+M shortcut)
- Save/restore window size when toggling compact mode
- Handle display scaling by converting physical to logical pixels
- Add compact_mode to config (Rust + TypeScript)
- Add required Tauri window permissions for resize operations

src-tauri/capabilities/default.json

@@ -19,6 +19,9 @@
     "core:tray:default",
     "fs:default",
     "fs:allow-read-text-file",
-    "fs:allow-write-text-file"
+    "fs:allow-write-text-file",
+    "core:window:allow-set-size",
+    "core:window:allow-set-always-on-top",
+    "core:window:allow-inner-size"
   ]
 }

src-tauri/src/config.rs

@@ -79,6 +79,9 @@ pub struct HikariConfig {
 
     #[serde(default)]
     pub streamer_hide_paths: bool,
+
+    #[serde(default)]
+    pub compact_mode: bool,
 }
 
 impl Default for HikariConfig {
@@ -101,6 +104,7 @@ impl Default for HikariConfig {
             minimize_to_tray: false,
             streamer_mode: false,
             streamer_hide_paths: false,
+            compact_mode: false,
         }
     }
 }
@@ -157,6 +161,7 @@ mod tests {
         assert!(!config.minimize_to_tray);
         assert!(!config.streamer_mode);
         assert!(!config.streamer_hide_paths);
+        assert!(!config.compact_mode);
     }
 
     #[test]
@@ -177,6 +182,9 @@ mod tests {
             character_panel_width: Some(400),
             font_size: 16,
             minimize_to_tray: true,
+            streamer_mode: false,
+            streamer_hide_paths: false,
+            compact_mode: false,
         };
 
         let json = serde_json::to_string(&config).unwrap();