batch4.1-5.1: dedup audit, archive 400 fix, sidebar Delete, landing-page enrichment, auto-name tool-call fix

- Fastify global empty-JSON-body parser fixes archive/unarchive/stop 400s
- Removed redundant local sessionEvents.emit at all 5+2 sites with server-side WS publishers; added dedupe guards in useSidebar/Workspace/Project handlers
- Sidebar session right-click adds Delete (destructive) with confirm Dialog
- Session.tsx navigates away on session_deleted/session_archived for the active session
- SessionLandingPage chat rows show message_count, effective_context_tokens, last_message_preview via LATERAL joins on GET /api/sessions/:id/chats
- Workspace.tsx pane drag-to-reorder using native HTML5 events (no new deps)
- CompactCard: Copy toast, Send-to-chat with target chat name, empty-state in share popover, Re-run button
- auto_name.ts: filter count gate and assistant-fetch by content <> '' so tool-call assistant rows don't trip the once-and-only-once guard
- Adds CLAUDE.md and apps/web/src/lib/format.ts

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/web/src/components/AddProjectModal.tsx

@@ -1,7 +1,6 @@
 import { useEffect, useState } from 'react';
 import { api } from '@/api/client';
 import type { AvailableProject } from '@/api/types';
-import { sessionEvents } from '@/hooks/sessionEvents';
 import { Button } from '@/components/ui/button';
 import {
   Dialog,
@@ -43,8 +42,8 @@ export function AddProjectModal({ open, onOpenChange, onAdded }: Props) {
     setBusy(true);
     setError(null);
     try {
-      const created = await api.projects.add({ path });
-      sessionEvents.emit({ type: 'project_created', project: created });
+      await api.projects.add({ path });
+      // Server publishes project_created via WS; let useUserEvents deliver it.
       onAdded();
       onOpenChange(false);
     } catch (err) {