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).

examples/acp-agent/tests/fixtures/subagent-durability-failure.ts

@@ -84,13 +84,13 @@ export function apply(ctx: Context): void {
   // runs, so the queued FIFO order is what the transcript records. The first
   // child enqueue is the initial delegation, which also pins the real child id.
   let accepted = 0
-  ctx.on('agent/inbox/inserted', (agent) => {
+  ctx.on('agent/inbox/inserted', ({ agent }) => {
     if (agent.session.header.parentSession === undefined) return
     if (realChildId === undefined) realChildId = agent.session.header.id
     accepted += 1
     if (accepted >= 3) followupsAccepted.resolve(undefined)
   })
-  ctx.on('agent/pre-step', async (agent, _messages, _context, next) => {
+  ctx.on('agent/pre-step', async ({ agent }, next) => {
     if (agent.session.header.parentSession !== undefined) await followupsAccepted.promise
     return next()
   })