batch4: chats-in-sessions, force-send, /compact, right-rail file browser

Session 1:N Chat data model with backfill. Workspace switches to client-side
multi-tab pane management. Right-rail file browser with float-over viewer and
click-drag line selection replaces FileBrowserPane. Adds /compact streaming
summarizer (respects compact markers in context builder), force-send (cancels
in-flight, persists partial as 'cancelled', awaits cancellation completion via
deferred Promise + 5s timeout), message queue, stop generation, chat
auto-rename, session archive/unarchive with Closed Sessions section on repo
landing page. CHECK constraints on sessions.status, messages.role,
messages.status with KEEP IN SYNC comments tying to MESSAGE_ROLES /
MESSAGE_STATUSES const arrays. Deletes dead pane routes/hook and the
api.panes.* client block.

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

apps/server/src/routes/chats.ts

@@ -0,0 +1,147 @@
+import type { FastifyInstance } from 'fastify';
+import { z } from 'zod';
+import type { Sql } from '../db.js';
+import type { Broker } from '../services/broker.js';
+import type { Chat, Message } from '../types/api.js';
+
+const CreateBody = z.object({
+  name: z.string().min(1).max(200).optional(),
+});
+
+const PatchBody = z.object({
+  name: z.string().min(1).max(200).optional(),
+  status: z.enum(['open', 'closed']).optional(),
+});
+
+export function registerChatRoutes(
+  app: FastifyInstance,
+  sql: Sql,
+  broker: Broker
+): void {
+  app.get<{ Params: { id: string } }>(
+    '/api/sessions/:id/chats',
+    async (req, reply) => {
+      const session = await sql`SELECT id FROM sessions WHERE id = ${req.params.id}`;
+      if (session.length === 0) {
+        reply.code(404);
+        return { error: 'session not found' };
+      }
+      const rows = await sql<Chat[]>`
+        SELECT id, session_id, name, status, created_at, updated_at
+        FROM chats
+        WHERE session_id = ${req.params.id}
+        ORDER BY updated_at DESC
+      `;
+      return rows;
+    }
+  );
+
+  app.post<{ Params: { id: string } }>(
+    '/api/sessions/:id/chats',
+    async (req, reply) => {
+      const parsed = CreateBody.safeParse(req.body ?? {});
+      if (!parsed.success) {
+        reply.code(400);
+        return { error: 'invalid body', details: parsed.error.flatten() };
+      }
+      const session = await sql`SELECT id FROM sessions WHERE id = ${req.params.id}`;
+      if (session.length === 0) {
+        reply.code(404);
+        return { error: 'session not found' };
+      }
+      const [chat] = await sql<Chat[]>`
+        INSERT INTO chats (session_id, name, status)
+        VALUES (${req.params.id}, ${parsed.data.name ?? null}, 'open')
+        RETURNING id, session_id, name, status, created_at, updated_at
+      `;
+      broker.publishUser('default', {
+        type: 'chat_created',
+        chat: chat!,
+        session_id: req.params.id,
+      });
+      reply.code(201);
+      return chat;
+    }
+  );
+
+  app.patch<{ Params: { id: string } }>(
+    '/api/chats/:id',
+    async (req, reply) => {
+      const parsed = PatchBody.safeParse(req.body ?? {});
+      if (!parsed.success) {
+        reply.code(400);
+        return { error: 'invalid body', details: parsed.error.flatten() };
+      }
+      const { name, status } = parsed.data;
+      if (name === undefined && status === undefined) {
+        reply.code(400);
+        return { error: 'must provide name or status' };
+      }
+      const rows = await sql<Chat[]>`
+        UPDATE chats
+        SET
+          name = COALESCE(${name ?? null}, name),
+          status = COALESCE(${status ?? null}, status),
+          updated_at = clock_timestamp()
+        WHERE id = ${req.params.id}
+        RETURNING id, session_id, name, status, created_at, updated_at
+      `;
+      if (rows.length === 0) {
+        reply.code(404);
+        return { error: 'chat not found' };
+      }
+      const chat = rows[0]!;
+      if (status === 'closed') {
+        broker.publishUser('default', {
+          type: 'chat_closed',
+          chat_id: chat.id,
+          session_id: chat.session_id,
+        });
+      } else {
+        broker.publishUser('default', {
+          type: 'chat_updated',
+          chat_id: chat.id,
+          session_id: chat.session_id,
+          name: chat.name,
+          updated_at: chat.updated_at,
+        });
+      }
+      return chat;
+    }
+  );
+
+  app.delete<{ Params: { id: string } }>(
+    '/api/chats/:id',
+    async (req, reply) => {
+      const result = await sql<{ id: string; session_id: string }[]>`
+        DELETE FROM chats WHERE id = ${req.params.id}
+        RETURNING id, session_id
+      `;
+      if (result.length === 0) {
+        reply.code(404);
+        return { error: 'chat not found' };
+      }
+      reply.code(204);
+      return null;
+    }
+  );
+
+  app.get<{ Params: { id: string } }>(
+    '/api/chats/:id/messages',
+    async (req, reply) => {
+      const chat = await sql`SELECT id FROM chats WHERE id = ${req.params.id}`;
+      if (chat.length === 0) {
+        reply.code(404);
+        return { error: 'chat not found' };
+      }
+      const rows = await sql<Message[]>`
+        SELECT id, session_id, chat_id, role, content, kind, tool_calls, tool_results, status, last_seq,
+               tokens_used, ctx_used, ctx_max, started_at, finished_at, created_at
+        FROM messages
+        WHERE chat_id = ${req.params.id}
+        ORDER BY created_at ASC, id ASC
+      `;
+      return rows;
+    }
+  );
+}