chore: sync the frontend template from 4dc033c to 8157ad4

The product was materialized from the template at `4dc033c` and has stayed
on it through 43 template commits, so it was missing all three rounds of
adapter remediation — including files it never had, such as the shared
`abortable-operation` primitive and the `exact-snapshot` decoder that
later fixes are written against. Taking only the newest round was not
possible for that reason: the delta is coherent only as a whole.

The product had not touched `src/adapters` at all since materialization,
so the 140-file delta applied with a three-way merge and no conflicts.
`package.json` was the single overlap and merged cleanly: the product owns
`name`, the template contributed `check:adapter-inventory`,
`check:remediation-ledger` and the image-resolve-signal type fixture.
All 24 product-owned files — README, index.html, CI workflow, i18n
catalog, home page, generated schemas, evidence scripts, component and
visual snapshots — are byte-identical to `main`.

`template.lock.json` now pins the synced revision and tree.

Verified in this repository, not inherited from the template: six type
projects, lint, nine gates (adapter inventory, remediation ledger,
registries, diagnostics, realtime boundaries, architecture, browser
file/storage boundaries, optional recipes, documentation), the production
build, and 2,054 of 2,073 tests. The 19 failures are all in
`tests/unit/ci-artifact-contract.test.ts` and are the same pre-existing
sandbox RLIMIT, EMFILE, umask and `/tmp` permission behaviour the template
records; four suites that failed once under parallel load pass in
isolation.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

docs/architecture/decisions/VD-28-realtime-events-web-push-and-bounded-polling.md

@@ -11,6 +11,26 @@
   첫 제품 stream/Web Push를 선택할 때, 또는 backend replay/hosting/provider
   protocol이 바뀔 때
 
+
+## 스트림 lifecycle은 freshness와 직교한다 (R-02, R-03)
+
+`RealtimeStreamLifecycle = OPEN | DRAINING | CLOSED`는 freshness
+(`UNKNOWN/CURRENT/STALE/RESYNCING`)와 별개다.
+
+- effect/recovery deadline에 도달하면 commit capability를 즉시 영구 무효화하고
+  abort한다. caller에는 bounded `IDLE_TIMEOUT`(non-retryable, operation
+  `APPLY`/`RECOVER`)을 반환하되 **실제 task는 버리지 않고 retain**한다.
+- retain된 task가 하나라도 있으면 stream은 `DRAINING`이고 새 event/recovery
+  admission을 거절한다. 실제 settlement가 일어나야 `STALE`로 돌아가
+  authoritative recovery를 요구하거나, close 요청이면 `CLOSED`가 된다.
+- `close()`는 `Promise<RealtimeResult<void>>`다. 모든 retain task가 실제로
+  settle해야 success이고, drain bound를 넘기면 `IDLE_TIMEOUT/CLOSE`를 반환하며
+  stream은 계속 `DRAINING`이다. teardown success가 곧 quiescence다.
+- LIVE↔POLL overflow fail-close는 active/probe/quiescing/transition lease를
+  모두 abort한 뒤 **retired writer set**으로 옮기고 나서 reference를 지운다.
+  `close()`는 current와 retired를 dedupe해 함께 기다리므로, 버려진
+  non-cooperative writer가 아직 실행 중인데 close가 성공을 보고할 수 없다.
+
 ## 배경
 
 현재 optional recipe catalog는 realtime capability에