Merge branch 'stack/agent-profiles-5-web-ui' into stack/agent-profiles-8-authoring

The composer's preset seat stays removed here — this layer moved it to the
hero chip and the session-header action — so only the model seat takes the
`modelSeatLocked` narrowing master introduced.

Conflicts:
	apps/web/tests/snapshots/*/*.expected.md
	packages/client/connection/README.md
	packages/client/connection/README.zh.md
	packages/client/ui-conversation/src/client/skeleton/InputBar.tsx
	packages/host/apiproxy/src/fetch/client.ts

packages/client/connection/src/index.ts

@@ -7,15 +7,26 @@ import { toFetchHandler } from '@deepseek-ai/dsh-host-apiproxy'
 import { API_PATH, HOST_EVENTS_PATH, MUX_EVENTS_PATH } from './api-path.ts'
 import { bridge } from './http-bridge.ts'
 import { assertTrustedAuthority, isTrustedApiRequest } from './api-request-trust.ts'
+import { HostConnectionService } from './rpc-host.ts'
 import { rejectWebSocketUpgrade, WebSocketDownlinks } from './websocket-downlink.ts'
 
+export type {
+  ConnectionRpcAuthority,
+  ConnectionRpcEndpointMatcher,
+  ConnectionRpcHandler,
+  ConnectionRpcHandlerOptions,
+  HostConnectionHandle,
+  HostConnectionRpc,
+} from './rpc.ts'
+export { HostConnectionService } from './rpc-host.ts'
+
 export { API_PATH, HOST_EVENTS_PATH, MUX_EVENTS_PATH } from './api-path.ts'
 
 /** Stable Cordis plugin name. */
 export const name = 'client-connection'
 
-/** Services required before mounting the route. */
-export const inject = ['httpServer', 'apiProxy']
+/** Services required before providing Connection; API Proxy is an optional `/api` fallback. */
+export const inject = ['httpServer']
 
 /** Plugin config: the deployment's non-loopback serving authorities. */
 export interface ConnectionConfig {
@@ -98,49 +109,61 @@ export function apply(ctx: Context, config?: ConnectionConfig): void {
   // Config boundary: a malformed entry fails the load loudly here rather than
   // silently authorizing its hostname prefix at request time.
   for (const entry of trustedHosts) assertTrustedAuthority(entry)
-  const apiHandler = toFetchHandler(ctx.apiProxy)
-  const downlinks = new WebSocketDownlinks(ctx.apiProxy)
+  const connection = new HostConnectionService(ctx, trustedHosts)
+  const fetchHandler = connection.createSharedFetchHandler(API_PATH, {
+    async fetch(request) {
+      const pathname = new URL(request.url).pathname
+      const method = pathname.startsWith(`${API_PATH}/`)
+        ? pathname.slice(API_PATH.length + 1)
+        : undefined
+      if (method !== undefined
+        && PRIVILEGED_METHODS.has(method)
+        && !isTrustedApiRequest(request, [])) {
+        return new Response('forbidden', { status: 403 })
+      }
+      if (request.method === 'GET' && (pathname === MUX_EVENTS_PATH || pathname === HOST_EVENTS_PATH)) {
+        return new Response('upgrade required', {
+          status: 426,
+          headers: { connection: 'Upgrade', upgrade: 'websocket' },
+        })
+      }
+      const apiProxy = ctx.get('apiProxy')
+      if (apiProxy === undefined) return new Response('not found', { status: 404 })
+      return toFetchHandler(apiProxy).fetch(request)
+    },
+  })
   const route: WebRoute = {
     kind: 'prefix',
     path: API_PATH,
     handler: async (req, res) => {
-      const pathname = new URL(req.url ?? '/', 'http://dsh.internal').pathname
-      const method = pathname.startsWith(`${API_PATH}/`)
-        ? pathname.slice(API_PATH.length + 1)
-        : undefined
-      const allowed = method !== undefined && PRIVILEGED_METHODS.has(method)
-        ? isTrustedApiRequest(req, [])
-        : isTrustedApiRequest(req, trustedHosts)
-      if (!allowed) {
+      if (!isTrustedApiRequest(req, trustedHosts)) {
         res.writeHead(403)
         res.end('forbidden')
         return
       }
-      if (req.method === 'GET' && (pathname === MUX_EVENTS_PATH || pathname === HOST_EVENTS_PATH)) {
-        res.writeHead(426, { connection: 'Upgrade', upgrade: 'websocket' })
-        res.end('upgrade required')
-        return
-      }
-      await bridge(req, res, apiHandler)
+      await bridge(req, res, fetchHandler)
     },
   }
   ctx.effect(() => ctx.httpServer.register(route), 'client-connection: /api route')
-  const registerDownlink = (
-    path: string,
-    handle: WebUpgradeRoute['handler'],
-  ): void => {
-    ctx.effect(() => ctx.httpServer.registerUpgrade({
-      path,
-      handler: (req, socket, head) => {
-        if (!isTrustedApiRequest(req, trustedHosts)) {
-          rejectWebSocketUpgrade(socket)
-          return
-        }
-        return handle(req, socket, head)
-      },
-    }), `client-connection: ${path} WebSocket`)
-  }
-  ctx.effect(() => () => downlinks.close(), 'client-connection: WebSocket downlinks')
-  registerDownlink(MUX_EVENTS_PATH, (req, socket, head) => { downlinks.handleMux(req, socket, head) })
-  registerDownlink(HOST_EVENTS_PATH, (req, socket, head) => { downlinks.handleHost(req, socket, head) })
+  ctx.inject(['apiProxy'], (apiCtx) => {
+    const downlinks = new WebSocketDownlinks(apiCtx.apiProxy)
+    const registerDownlink = (
+      path: string,
+      handle: WebUpgradeRoute['handler'],
+    ): void => {
+      apiCtx.effect(() => apiCtx.httpServer.registerUpgrade({
+        path,
+        handler: (req, socket, head) => {
+          if (!isTrustedApiRequest(req, trustedHosts)) {
+            rejectWebSocketUpgrade(socket)
+            return
+          }
+          return handle(req, socket, head)
+        },
+      }), `client-connection: ${path} WebSocket`)
+    }
+    apiCtx.effect(() => () => downlinks.close(), 'client-connection: WebSocket downlinks')
+    registerDownlink(MUX_EVENTS_PATH, (req, socket, head) => { downlinks.handleMux(req, socket, head) })
+    registerDownlink(HOST_EVENTS_PATH, (req, socket, head) => { downlinks.handleHost(req, socket, head) })
+  })
 }