v1.4-fork-header: fork from message + delete message + header polish + housekeeping

- Fork: POST /api/chats/:id/fork creates a new chat in the same session,
  copies messages up to target (status=complete) with row-offset
  clock_timestamp() for stable ordering. Client emits open_chat_in_active_pane
  event; Workspace opens it in the active pane. No maybeAutoNameChat on forks.
- Delete: DELETE /api/chats/:id/messages/:message_id with 409 if the chat is
  currently streaming. Cascading-forward delete (created_at >= target).
  MessageBubble Trash button + confirm Dialog.
- Header: Projects -> Project -> Session breadcrumb, model badge pill,
  inline session rename, active file path via new useActivePane() hook.
  Server now publishes session_renamed on PATCH /api/sessions/:id;
  client-side dup emit removed from Session.tsx.
- Housekeeping: NOW() -> clock_timestamp() in schema.sql defaults, dead
  PaneTab.tsx and panes/PaneShell.tsx removed, session_panes backfill
  INSERT removed (CREATE TABLE retained), Tailnet trust comment near
  app.listen().

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

apps/web/src/pages/Session.tsx

@@ -1,9 +1,10 @@
 import { useEffect, useState } from 'react';
 import { Link, useNavigate, useParams } from 'react-router-dom';
-import { ChevronLeft } from 'lucide-react';
+import { ChevronRight } from 'lucide-react';
 import { api } from '@/api/client';
-import type { Session as SessionType } from '@/api/types';
+import type { Project, Session as SessionType } from '@/api/types';
 import { sessionEvents } from '@/hooks/sessionEvents';
+import { useActivePane } from '@/hooks/useActivePane';
 import { Workspace } from '@/components/Workspace';
 import { ModelPicker } from '@/components/ModelPicker';
 
@@ -11,12 +12,15 @@ export function Session() {
   const { id } = useParams<{ id: string }>();
   const navigate = useNavigate();
   const [session, setSession] = useState<SessionType | null>(null);
+  const [project, setProject] = useState<Project | null>(null);
   const [name, setName] = useState('');
   const [editingName, setEditingName] = useState(false);
+  const active = useActivePane();
 
   useEffect(() => {
     if (!id) return;
     setSession(null);
+    setProject(null);
     let cancelled = false;
     api.sessions
       .get(id)
@@ -24,16 +28,17 @@ export function Session() {
         if (cancelled) return;
         setSession(s);
         setName(s.name);
-        // Emit unconditionally — the sidebar's session_loaded handler
-        // updates activeSession; redundant when the session is already in
-        // the recent_sessions cache but harmless. This lets the sidebar
-        // highlight the parent project for deep-linked sessions that
-        // aren't in the cache.
         sessionEvents.emit({
           type: 'session_loaded',
           session_id: id,
           project_id: s.project_id,
         });
+        // Load project for breadcrumb. Listing is fine — small N, cached by client.
+        api.projects.list().then((projects) => {
+          if (cancelled) return;
+          const p = projects.find((x) => x.id === s.project_id);
+          if (p) setProject(p);
+        }).catch(() => {});
       })
       .catch(() => {});
     return () => {
@@ -68,26 +73,33 @@ export function Session() {
     }
     const updated = await api.sessions.update(id, { name: trimmed });
     setSession(updated);
-    sessionEvents.emit({
-      type: 'session_renamed',
-      session_id: id,
-      name: trimmed,
-    });
     setEditingName(false);
+    // Server publishes session_renamed via broker.publishUser; no local emit needed.
   }
 
+  // Workspace only sets activeFile for file-browser panes; checking it alone
+  // suffices and is forward-compatible with future pane kinds.
+  const showActiveFile = active.sessionId === id && !!active.activeFile;
+
   return (
     <div className="flex-1 flex flex-col min-h-0">
-      <header className="border-b px-4 py-2 flex items-center gap-2 shrink-0">
-        {session && (
+      <header className="border-b px-4 py-2 flex items-center gap-1.5 shrink-0 text-sm">
+        <Link to="/" className="text-muted-foreground hover:text-foreground">
+          Projects
+        </Link>
+        <ChevronRight className="size-3 text-muted-foreground/60" />
+        {project ? (
           <Link
-            to={`/project/${session.project_id}`}
-            className="text-muted-foreground hover:text-foreground"
-            aria-label="Back to project"
+            to={`/project/${project.id}`}
+            className="text-muted-foreground hover:text-foreground truncate max-w-[200px]"
+            title={project.name}
           >
-            <ChevronLeft className="size-4" />
+            {project.name}
           </Link>
+        ) : (
+          <span className="text-muted-foreground/60">…</span>
         )}
+        <ChevronRight className="size-3 text-muted-foreground/60" />
         {editingName ? (
           <input
             autoFocus
@@ -106,21 +118,35 @@ export function Session() {
         ) : (
           <button
             type="button"
-            className="text-sm font-medium hover:underline"
+            className="text-sm font-medium hover:underline truncate max-w-[280px]"
             onClick={() => setEditingName(true)}
+            title={session?.name ?? ''}
           >
             {session?.name ?? '…'}
           </button>
         )}
+        {showActiveFile && active.activeFile && (
+          <>
+            <span className="text-muted-foreground/40 mx-1">·</span>
+            <span
+              className="text-xs font-mono text-muted-foreground truncate max-w-[320px]"
+              title={active.activeFile}
+            >
+              {active.activeFile}
+            </span>
+          </>
+        )}
         <div className="ml-auto">
           {session && (
-            <ModelPicker
-              value={session.model}
-              onChange={async (model) => {
-                const updated = await api.sessions.update(session.id, { model });
-                setSession(updated);
-              }}
-            />
+            <div className="inline-flex items-center rounded-full bg-muted/40 hover:bg-muted/70 px-1">
+              <ModelPicker
+                value={session.model}
+                onChange={async (model) => {
+                  const updated = await api.sessions.update(session.id, { model });
+                  setSession(updated);
+                }}
+              />
+            </div>
           )}
         </div>
       </header>