feat: add native clipboard support for screenshot paste

- Add Tauri clipboard-manager plugin for native clipboard access
- Fall back to native clipboard when WebView clipboard API returns empty
- Convert RGBA image data to PNG via canvas for saving
- Allow sending messages with attachments only (no text required)
- Log attached files to output with 📎 emoji
- Update send button to enable when attachments exist

Co-Authored-By: Naomi Carrigan <commits@nhcarrigan.com>

src/lib/components/InputBar.svelte

@@ -1,6 +1,7 @@
 <script lang="ts">
   import { invoke } from "@tauri-apps/api/core";
   import { open } from "@tauri-apps/plugin-dialog";
+  import { readImage } from "@tauri-apps/plugin-clipboard-manager";
   import { get } from "svelte/store";
   import { claudeStore, isClaudeProcessing } from "$lib/stores/claude";
   import { characterState } from "$lib/stores/character";
@@ -165,10 +166,13 @@
     event.preventDefault();
 
     const message = inputValue.trim();
-    if (!message || isSubmitting) return;
+    const hasAttachments = attachments.length > 0;
+
+    // Need either a message or attachments to submit
+    if ((!message && !hasAttachments) || isSubmitting) return;
 
     // Check for slash commands first (these work even when disconnected)
-    if (isSlashCommand(message)) {
+    if (message && isSlashCommand(message)) {
       // Add slash commands to history too
       addToHistory(message);
       historyIndex = -1;
@@ -189,8 +193,10 @@
     // Regular messages require connection
     if (!isConnected) return;
 
-    // Add to history before clearing
-    addToHistory(message);
+    // Add to history before clearing (only if there's text)
+    if (message) {
+      addToHistory(message);
+    }
     historyIndex = -1;
     tempInput = "";
     userHasTyped = false;
@@ -198,12 +204,33 @@
     isSubmitting = true;
     inputValue = "";
 
-    // Apply mode prefix if needed
+    // Capture attachments before clearing
+    const currentAttachments = [...attachments];
+
+    // Apply mode prefix if needed (only if there's a message)
     const currentMode = getCurrentMode();
-    const formattedMessage = formatMessageWithMode(message, currentMode);
+    const formattedMessage = message ? formatMessageWithMode(message, currentMode) : "";
+
+    // Build message with attachments
+    let messageWithAttachments = formattedMessage;
+    if (currentAttachments.length > 0) {
+      const attachmentPaths = currentAttachments.map((a) => a.path).join("\n");
+      const attachmentPrefix = formattedMessage
+        ? `${formattedMessage}\n\n`
+        : "";
+      messageWithAttachments = `${attachmentPrefix}[Attached files - please read these files to see their contents:]\n${attachmentPaths}`;
+
+      // Log attached files to the output
+      for (const attachment of currentAttachments) {
+        claudeStore.addLine("system", `📎 Attached: ${attachment.filename} (${attachment.path})`);
+      }
+    }
+
+    // Clear attachments after capturing them
+    claudeStore.clearAttachments();
 
     // Check if we need to restore conversation history
-    let messageToSend = formattedMessage;
+    let messageToSend = messageWithAttachments;
     if (getShouldRestoreHistory()) {
       const savedHistory = getSavedHistory();
 
@@ -341,7 +368,7 @@ User: ${formattedMessage}`;
     }
   }
 
-  function handleDrop(event: DragEvent) {
+  async function handleDrop(event: DragEvent) {
     event.preventDefault();
     event.stopPropagation();
     isDragging = false;
@@ -349,6 +376,8 @@ User: ${formattedMessage}`;
     const files = event.dataTransfer?.files;
     if (!files || files.length === 0) return;
 
+    const conversationId = get(claudeStore.activeConversationId);
+
     for (const file of files) {
       const filename = file.name;
       const extension = filename.split(".").pop()?.toLowerCase() || "";
@@ -361,10 +390,29 @@ User: ${formattedMessage}`;
         previewUrl = URL.createObjectURL(file);
       }
 
+      // Check if the file has a native path (from Tauri's file drop)
+      // If not, we need to save it to a temp file
+      let savedPath = (file as File & { path?: string }).path;
+
+      if (!savedPath && conversationId) {
+        try {
+          const arrayBuffer = await file.arrayBuffer();
+          const bytes = Array.from(new Uint8Array(arrayBuffer));
+          savedPath = await invoke<string>("save_temp_file", {
+            conversationId,
+            filename,
+            data: bytes,
+          });
+        } catch (error) {
+          console.error("Failed to save dropped file to temp:", error);
+          savedPath = file.name;
+        }
+      }
+
       const attachment: Attachment = {
         id: `attachment-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
         filename,
-        path: (file as File & { path?: string }).path || file.name,
+        path: savedPath || file.name,
         size: file.size,
         type: fileType,
         mimeType: file.type,
@@ -441,40 +489,124 @@ User: ${formattedMessage}`;
     }
   }
 
-  function handlePaste(event: ClipboardEvent) {
+  async function handlePaste(event: ClipboardEvent) {
+    // First, try the web clipboard API for files
     const items = event.clipboardData?.items;
-    if (!items) return;
+    let handledFile = false;
 
-    for (const item of items) {
-      // Check if the item is a file (image or other)
-      if (item.kind === "file") {
-        const file = item.getAsFile();
-        if (!file) continue;
+    if (items && items.length > 0) {
+      for (const item of items) {
+        if (item.kind === "file") {
+          const file = item.getAsFile();
+          if (!file) continue;
 
-        // Prevent default for file pastes so we handle it
-        event.preventDefault();
+          event.preventDefault();
+          handledFile = true;
 
-        const filename = file.name || `pasted-${Date.now()}.${file.type.split("/")[1] || "png"}`;
-        const extension = filename.split(".").pop()?.toLowerCase() || "";
-        const fileType = getFileTypeFromExtension(extension);
+          const filename = file.name || `pasted-${Date.now()}.${file.type.split("/")[1] || "png"}`;
+          const extension = filename.split(".").pop()?.toLowerCase() || "";
+          const fileType = getFileTypeFromExtension(extension);
 
-        // Create preview URL for images
-        let previewUrl: string | undefined;
-        if (fileType === "image" || file.type.startsWith("image/")) {
-          previewUrl = URL.createObjectURL(file);
+          let previewUrl: string | undefined;
+          if (fileType === "image" || file.type.startsWith("image/")) {
+            previewUrl = URL.createObjectURL(file);
+          }
+
+          const conversationId = get(claudeStore.activeConversationId);
+          let savedPath = filename;
+
+          if (conversationId) {
+            try {
+              const arrayBuffer = await file.arrayBuffer();
+              const bytes = Array.from(new Uint8Array(arrayBuffer));
+              savedPath = await invoke<string>("save_temp_file", {
+                conversationId,
+                filename,
+                data: bytes,
+              });
+            } catch (error) {
+              console.error("Failed to save pasted file to temp:", error);
+            }
+          }
+
+          const attachment: Attachment = {
+            id: `attachment-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
+            filename,
+            path: savedPath,
+            size: file.size,
+            type: file.type.startsWith("image/") ? "image" : fileType,
+            mimeType: file.type,
+            previewUrl,
+          };
+
+          claudeStore.addAttachment(attachment);
         }
+      }
+    }
 
-        const attachment: Attachment = {
-          id: `attachment-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
-          filename,
-          path: filename,
-          size: file.size,
-          type: file.type.startsWith("image/") ? "image" : fileType,
-          mimeType: file.type,
-          previewUrl,
-        };
+    // If web clipboard didn't have files, try Tauri's native clipboard for images
+    if (!handledFile) {
+      try {
+        const image = await readImage();
+        const rgba = await image.rgba();
+        const size = await image.size();
 
-        claudeStore.addAttachment(attachment);
+        if (rgba && rgba.length > 0) {
+          event.preventDefault();
+
+          const conversationId = get(claudeStore.activeConversationId);
+          const filename = `screenshot-${Date.now()}.png`;
+
+          // Convert RGBA to PNG using canvas
+          const canvas = document.createElement("canvas");
+          canvas.width = size.width;
+          canvas.height = size.height;
+          const ctx = canvas.getContext("2d");
+
+          if (ctx) {
+            const imgData = ctx.createImageData(size.width, size.height);
+            imgData.data.set(new Uint8ClampedArray(rgba));
+            ctx.putImageData(imgData, 0, 0);
+
+            // Create preview URL from canvas
+            const previewUrl = canvas.toDataURL("image/png");
+
+            // Convert to blob for saving
+            const blob = await new Promise<Blob | null>((resolve) =>
+              canvas.toBlob(resolve, "image/png")
+            );
+
+            let savedPath = filename;
+            if (blob && conversationId) {
+              try {
+                const arrayBuffer = await blob.arrayBuffer();
+                const bytes = Array.from(new Uint8Array(arrayBuffer));
+                savedPath = await invoke<string>("save_temp_file", {
+                  conversationId,
+                  filename,
+                  data: bytes,
+                });
+              } catch (error) {
+                console.error("Failed to save clipboard image to temp:", error);
+              }
+            }
+
+            const attachment: Attachment = {
+              id: `attachment-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
+              filename,
+              path: savedPath,
+              size: blob?.size || 0,
+              type: "image",
+              mimeType: "image/png",
+              previewUrl,
+            };
+
+            claudeStore.addAttachment(attachment);
+          }
+        }
+      } catch (error) {
+        // No image in clipboard or clipboard read failed - that's fine, just ignore
+        console.log("No image in native clipboard:", error);
       }
     }
   }
@@ -619,7 +751,7 @@ User: ${formattedMessage}`;
       {:else}
         <button
           type="submit"
-          disabled={!isConnected || isSubmitting || !inputValue.trim()}
+          disabled={!isConnected || isSubmitting || (!inputValue.trim() && attachments.length === 0)}
           class="send-button bg-[var(--accent-primary)] hover:bg-[var(--accent-secondary)]
                disabled:opacity-50 disabled:cursor-not-allowed"
         >