feat: improve VS Code dev flow and stabilize sidebar/chat behavior (#754)

* fix: improve session sidebar tooltip and truncation behavior

- Keep new-draft tooltip anchored to its trigger button
- Fix minimal-mode worktree/group header text truncation
- Tune minimal-mode right padding to reduce early label clipping

* fix: render reasoning through markdown pipeline

- Use Streamdown rendering for reasoning in live chat mode
- Remove italic styling from reasoning text
- Render expanded reasoning content with MarkdownRenderer

* chore: remove legacy electron dependencies

- Removed unused Electron packages from root and UI manifests
- Deleted obsolete Electron context menu type declaration
- Regenerated lockfile after dependency cleanup

* fix: handle non-repository folders in git status API

- Prevent 500 errors when status is requested outside a valid Git repo
- Improve repository detection using `git rev-parse --git-dir`
- Reduce noisy server logs for expected non-repo status checks

* fix unloaded session chat layout flicker

* fix: reduce noisy TTS status polling

Cache and dedupe TTS status requests, and only check provider availability when the related voice features are enabled so disabled voice setups stay quiet.

* perf: throttle background PR git status refreshes

* fix: improve VS Code Explorer file drop mentions in chat

- Add Explorer context action to insert selected files as @mentions.
- Handle Explorer drag-and-drop to prefill @file mentions instead of attachments.
- Prevent duplicate plain-path text when dropping multiple files.

* fix: deduplicate recent sessions in VS Code sidebar

- Hide sessions from main list when already shown in recent
- Apply dedup only in VS Code runtime
- Keep session search behavior unchanged

* feat: add true HMR dev flow for VS Code extension

- Load VS Code webview from Vite dev server with React refresh preamble
- Add `vscode:dev` runner that starts watchers and opens Extension Development Host
- Update VS Code dev docs and scripts to use the new HMR startup flow

* feat: polish VS Code session sidebar and attachment UX

- Add resizable sessions sidebar in VS Code layout
- Tighten session list spacing and hover behavior in VS Code
- Remove bulk file/image attach success toasts while keeping error toasts

packages/ui/src/components/session/SessionSidebar.tsx

@@ -1032,6 +1032,44 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     ];
   }, [activeNowSessions, sessionSidebarMetaById]);
 
+  const recentSessionIds = React.useMemo(() => {
+    return new Set(activitySections.flatMap((section) => section.items.map((item) => item.node.session.id)));
+  }, [activitySections]);
+
+  const sectionsForSidebarRender = React.useMemo(() => {
+    if (!isVSCode || hasSessionSearchQuery || recentSessionIds.size === 0) {
+      return sectionsForRender;
+    }
+
+    const filterNodes = (nodes: SessionNode[]): SessionNode[] => {
+      return nodes.reduce<SessionNode[]>((acc, node) => {
+        if (recentSessionIds.has(node.session.id)) {
+          return acc;
+        }
+
+        const filteredChildren = filterNodes(node.children);
+        if (filteredChildren.length === node.children.length) {
+          acc.push(node);
+          return acc;
+        }
+
+        acc.push({
+          ...node,
+          children: filteredChildren,
+        });
+        return acc;
+      }, []);
+    };
+
+    return sectionsForRender.map((section) => ({
+      ...section,
+      groups: section.groups.map((group) => ({
+        ...group,
+        sessions: filterNodes(group.sessions),
+      })),
+    }));
+  }, [isVSCode, hasSessionSearchQuery, recentSessionIds, sectionsForRender]);
+
   const desktopHeaderActionButtonClass =
     'inline-flex h-6 w-6 cursor-pointer items-center justify-center rounded-md leading-none text-foreground hover:bg-interactive-hover focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-primary/50 disabled:cursor-not-allowed';
   const mobileHeaderActionButtonClass =
@@ -1203,12 +1241,13 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
   }, [prStatusEntries]);
 
   const renderGroupSessions = React.useCallback(
-    (group: SessionGroup, groupKey: string, projectId?: string | null, hideGroupLabel?: boolean, dragHandleProps?: SortableDragHandleProps | null) => (
+    (group: SessionGroup, groupKey: string, projectId?: string | null, hideGroupLabel?: boolean, dragHandleProps?: SortableDragHandleProps | null, compactBodyPadding?: boolean) => (
       <SessionGroupSection
         group={group}
         groupKey={groupKey}
         projectId={projectId}
         hideGroupLabel={hideGroupLabel}
+        compactBodyPadding={compactBodyPadding}
         hasSessionSearchQuery={hasSessionSearchQuery}
         normalizedSessionSearchQuery={normalizedSessionSearchQuery}
         groupSearchDataByGroup={groupSearchDataByGroup}
@@ -1363,7 +1402,7 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
 
       <SidebarProjectsList
         topContent={topContent}
-        sectionsForRender={sectionsForRender}
+        sectionsForRender={sectionsForSidebarRender}
         projectSections={projectSections}
         activeProjectId={activeProjectId}
         showOnlyMainWorkspace={showOnlyMainWorkspace}