refactor(agent): unify agent-scoped event signatures as payload objects

All agent/* and agent-loop/config-start-failed events take one payload
object carrying the agent subject; waterfall/serial payloads require a
signal and keep next as the final argument. PreStepContext and
RequestFailureContext are unfolded into payloads and retired.
goal/changed follows the same shape so agentEvents keeps its listener
error containment. ReactLoopAgent builds its scope carrier once in the
constructor. Regenerates scope resolvers, tool-cordis api catalog, and
docs catalogs; updates all affected listeners, tests, and the
core-data-structures docs (en + zh).

apps/cli/src/headless.ts

@@ -111,7 +111,7 @@ export async function runHeadless(task: string): Promise<void> {
   const abort = new AbortController()
   const frames = api.events.mux({}, abort.signal)
   const idle = new Promise<void>((resolve) => {
-    ctx.on('agent/status', (agent, status) => {
+    ctx.on('agent/status', ({ agent, status }) => {
       if (agent.id === created.sessionId && status === 'idle') resolve()
     })
   })