fix(plugins): async shutdown and asset/RPC fixes

Await stopPluginServer/stopAllPlugins in signal handlers and route
handlers so process exit and state transitions wait for clean plugin
shutdown instead of racing ahead.

Validate asset paths are regular files before streaming to prevent
directory traversal returning unexpected content; add a stream error
handler to avoid unhandled crashes on read failures.

Fix RPC proxy body detection to use the content-length header instead
of Object.keys, so falsy but valid JSON payloads (null, false, 0, {})
are forwarded correctly to plugin servers.

Track in-flight start operations via a startingPlugins map to prevent
duplicate concurrent plugin starts.

src/components/git-panel/view/GitPanel.tsx

@@ -108,6 +108,7 @@ export default function GitPanel({ selectedProject, isMobile = false, onFileOpen
           {activeView === 'changes' && (
             <ChangesView
               isMobile={isMobile}
+              projectPath={selectedProject.fullPath}
               gitStatus={gitStatus}
               gitDiff={gitDiff}
               isLoading={isLoading}

src/components/git-panel/view/changes/ChangesView.tsx

@@ -9,6 +9,7 @@ import FileStatusLegend from './FileStatusLegend';
 
 type ChangesViewProps = {
   isMobile: boolean;
+  projectPath: string;
   gitStatus: GitStatusResponse | null;
   gitDiff: GitDiffMap;
   isLoading: boolean;
@@ -27,6 +28,7 @@ type ChangesViewProps = {
 
 export default function ChangesView({
   isMobile,
+  projectPath,
   gitStatus,
   gitDiff,
   isLoading,
@@ -131,6 +133,7 @@ export default function ChangesView({
     <>
       <CommitComposer
         isMobile={isMobile}
+        projectPath={projectPath}
         selectedFileCount={selectedFiles.size}
         isHidden={hasExpandedFiles}
         onCommit={commitSelectedFiles}

src/components/git-panel/view/changes/CommitComposer.tsx

@@ -1,10 +1,14 @@
 import { Check, ChevronDown, GitCommit, RefreshCw, Sparkles } from 'lucide-react';
-import { useState } from 'react';
+import { useCallback, useState } from 'react';
 import MicButton from '../../../mic-button/view/MicButton';
 import type { ConfirmationRequest } from '../../types/types';
 
+// Persists commit messages across unmount/remount, keyed by project path
+const commitMessageCache = new Map<string, string>();
+
 type CommitComposerProps = {
   isMobile: boolean;
+  projectPath: string;
   selectedFileCount: number;
   isHidden: boolean;
   onCommit: (message: string) => Promise<boolean>;
@@ -14,13 +18,26 @@ type CommitComposerProps = {
 
 export default function CommitComposer({
   isMobile,
+  projectPath,
   selectedFileCount,
   isHidden,
   onCommit,
   onGenerateMessage,
   onRequestConfirmation,
 }: CommitComposerProps) {
-  const [commitMessage, setCommitMessage] = useState('');
+  const [commitMessage, setCommitMessageState] = useState(() => commitMessageCache.get(projectPath) ?? '');
+
+  const setCommitMessage = useCallback(
+    (msg: string) => {
+      setCommitMessageState(msg);
+      if (msg) {
+        commitMessageCache.set(projectPath, msg);
+      } else {
+        commitMessageCache.delete(projectPath);
+      }
+    },
+    [projectPath],
+  );
   const [isCommitting, setIsCommitting] = useState(false);
   const [isGeneratingMessage, setIsGeneratingMessage] = useState(false);
   const [isCollapsed, setIsCollapsed] = useState(isMobile);