feat(agents): unify agent status into a durable progress_card (#125125)

feat(agents): unify agent status into a durable progress_card (#125125)

* feat(agents): unify agent status into a durable progress_card

Replace the write-only update_plan to-do tool and the fragmented plan
rendering with one durable status artifact per session: progress_card
({plan?, markdown?}, replace-on-write, 8 KiB markdown / 50-step caps).
Cards persist in a lazy-additive session_progress_cards table in the
per-agent DB (no schema-version bump), broadcast progressCard.changed,
and render from the store with exactly one live placement per view
(session rail when visible, else the composer-adjacent bar); transcripts
collapse to one-line receipts, and the sidebar hovercard shows other
sessions' cards inline (markdown + , DOMPurify allowlist, no
iframes). The three stream-derived plan renderers and their dedup
heuristics are deleted.

Codex runs disable the native plan tool per thread
(tools.update_plan.enabled=false) and receive progress_card via the
dynamic-tool bridge; compaction restore now reinjects the card (steps +
bounded markdown). Card writes still emit the legacy plan stream event so
native apps and channels keep working until their per-platform
migrations. Policy names map update_plan -> progress_card; the shipped
tools.updatePlan=false kill switch is honored.

Net -277 production LOC; -480 test LOC.

* test(agents): regenerate Codex prompt snapshots for update_plan thread-config disable

* chore(protocol): allowlist progressCard.changed for native apps pending card migration

* fix(ci): repair progress card integration checks

* fix(codex): canonicalize native progress cards

* test(gateway): reconcile progress card method order

* test(codex): stabilize native approval fixture