refactor(agent): publish agent/inbox/claimed from Inbox.claim

Move the claimed-message notification loop out of the loop's pre-step
into Inbox.claim(target, turn), so the step-boundary operation publishes
its own claimed notifications like insertions and discards do.

packages/pty/tool-pty/tests/loader-composition.spec.ts

@@ -40,8 +40,9 @@ function agent(ctx: Context): Agent {
   const id = SessionId('pty-loader-agent')
   const session = Session.create(id)
   const value: Agent = {
-    id, options: {}, session, inbox: new Inbox(session, { inserted: () => {}, discarded: () => {} }),
-    status: 'idle', ctx: scope.ctx,
+    id, options: {}, session, inbox: new Inbox(session, { inserted: () => {}, discarded: () => {}, claimed: () => {} }),
+    status: 'idle',
+    ctx: scope.ctx,
     send: () => {},
     followup: () => {}, steer: () => {}, inject: () => {}, cancel() {},
     runMaintenance: task => task(new AbortController().signal),

packages/pty/tool-pty/tests/tools.spec.ts

@@ -18,8 +18,9 @@ function fakeAgent(ctx: Context, rawId: string): Agent {
   const id = SessionId(rawId)
   const session = Session.create(id)
   const agent: Agent = {
-    id, options: {}, session, inbox: new Inbox(session, { inserted: () => {}, discarded: () => {} }),
-    status: 'idle', ctx: scope.ctx,
+    id, options: {}, session, inbox: new Inbox(session, { inserted: () => {}, discarded: () => {}, claimed: () => {} }),
+    status: 'idle',
+    ctx: scope.ctx,
     send: () => {},
     followup: () => {}, steer: () => {}, inject: () => {}, cancel() {},
     runMaintenance: task => task(new AbortController().signal),