fix: execute the 2026-08-19 audit fix order (docs refresh + five FRAGILE fixes) (#1396)

* docs(plans): phased remediation plan for the 2026-08-19 audit

Executes the audit's §8 MUST-fix verdict and §9.1 fix order: one phase per
finding group, statuses updated in place as phases land.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HtkxwdqE4pUv82GQPRsTeQ

* test(client): give the renderWindow-breaker test its own timeout (audit F-5)

30 synchronous 100-row jsdom rebuilds can exceed vitest's default 5s on a
loaded runner; the test timed out once under CI-like load and passes in
isolation, so it now carries an explicit 20s budget.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HtkxwdqE4pUv82GQPRsTeQ

* docs: fix the ten wrong reference-doc statements from audit 2026-08-19 (B-01..B-10)

schema.md: migrations 030/031 documented, attachments ON DELETE SET NULL
(matching 030's rebuild), index inventory rewritten from cumulative migration
state, writer/reader pool split described, default-roles table made a
consistent post-migration snapshot, dbgen preamble updated.

protocol.md: DM chat events documented as sequenced/ring-buffered/replayable
(they are), plugin_broadcast seq flipped to Yes, retry_after claim removed
(no WS error carries it), the five enforced-but-documented-as-None rate
limits added (channel_focus, mark_read, call_decline, chat_command, ping),
E2EE announce/offer budgets corrected incl. the per-target inner cap,
BAD_PAYLOAD and NOT_KEY_HOLDER added to the error table, ready voice_states/
roles field lists completed, member_join top-level status documented.

api.md: diagnostics endpoint is ADMINISTRATOR-only (H-8) with a per-IP
limiter and host:port livekit_url, error-code table now matches emitted codes
(INTERNAL_ERROR, STORAGE_ERROR 507; oversize upload is 400), body-cap
exemptions listed, identity_public_key documented on PATCH /users/me, plugin
endpoints' plain-text errors + X-Plugin-Runtime header documented, /health
503 degraded state documented, metrics/LiveKit CIDR keys named, updates/apply
restart-conflict 409s added.

Also folds in the audit's D-04/D-05 comment and plan-header staleness fixes
(buildReady comment, e2e spec-count comments, logctx stray word, three plan
status headers).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HtkxwdqE4pUv82GQPRsTeQ

* fix(server): log the five silently-discarded persistence errors (audit F-3/F-4/D-16)

Lockout Upsert/Delete/Cleanup failures (auth/ratelimit.go), the H-6
session-cap eviction failure in CreateSession (db/auth_queries.go), and the
channel_focus read-state write failure (service/channel.go) all discarded
their errors with no trace — a brute-force lockout could silently fail to
survive a restart. In-memory behavior is unchanged (warn-and-continue); the
lockout write paths are pinned by tests mirroring OC-0061's load-path test.
The session-cap and read-state sites are log-only additions on seams the
existing suites already exercise on the success path.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HtkxwdqE4pUv82GQPRsTeQ

* fix(dm): blocking a user evicts them from the pair's live 1:1 DM voice call (audit F-1)

The block gate ran only at voice_join and voluntary voice_token_refresh, so
a blocked user already in the shared 1:1 DM call kept their session
indefinitely — the same guard-asymmetry family as A-2026-08-03. handleBlockUser
now severs the call through the dmVoiceEvictor capability handleCloseDM
already exercises, using a new find-only FindDMChannelIDBetween lookup
(sqlc-generated; mirrors GetOrCreateDMChannel's is_group=0 clause so group
DM calls stay exempt, matching requireDMNotBlocked). Pinned by three handler
tests: shared-DM eviction, no-DM no-op, group-only no-op.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HtkxwdqE4pUv82GQPRsTeQ

* fix(ws): close the role-reassignment/handshake race (audit F-2)

A role reassignment landing mid-handshake was invisible for the socket's
whole life: both handshake paths resolved permissions from the auth-time
c.user snapshot, revokeUnreadableChannels early-returns for a user not yet
in h.clients, and its Unsubscribe no-ops on the pubsub identity guard once a
reconnect replaced the client.

Three coordinated fixes: (1) refreshUserSnapshot re-reads the user row (and
role name) in reconnectPrecheck and handleFreshConnect, fail-closed; (2) the
resume-fallback path re-reads the role once more after registerNow and runs
the revocation pass when it moved, so the reassignment-vs-registration
orderings meet in the middle; (3) revokeUnreadableChannels re-resolves the
live client immediately before acting, mirroring RefreshChannelVisibility.
Pinned by four tests driving real WS handshakes through the existing race
hooks plus a new pre-register/pre-act hook pair; ws suite green under the
default and deadlock builds.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HtkxwdqE4pUv82GQPRsTeQ

* refactor(client): remove the inert replay-dedup machinery (audit F-6)

The server writes auth_ok before the replay burst, so replayDedup — created
on socket-open and cleared when auth_ok is processed — could never be active
for a real replayed frame, and the dispatcher's isReplaying() unread gates
never fired. Their no-op behavior is the correct behavior (a buffer/db
resume has no ready payload, so replayed frames must count as unread), so
the machinery, the gates, and the misleading comments are removed rather
than repaired. The pinning tests injected replay frames in an order a
spec-compliant server never produces; they are replaced by a test pinning
the real contract (frames after auth_ok are dispatched verbatim; duplicate
handling belongs to the stores). Client suite green: 5036/5036.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HtkxwdqE4pUv82GQPRsTeQ

* docs(plans): mark remediation phases 1-6 done

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HtkxwdqE4pUv82GQPRsTeQ

* fix(ws): nolint the context-less revoke call golangci-lint flags

revokeUnreadableChannels takes no context by design (admin HubBroadcaster
interface); annotate the one call site inside a ctx-taking function, matching
the RefreshChannelVisibility precedent. golangci-lint v2.11.3: 0 issues.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HtkxwdqE4pUv82GQPRsTeQ

---------

Co-authored-by: Claude <noreply@anthropic.com>

Server/api/dm_handler.go

@@ -83,7 +83,7 @@ func MountDMRoutes(r chi.Router, database *db.DB, svc *service.Services, broadca
 	r.Route("/api/v1/blocks", func(r chi.Router) {
 		r.Use(AuthMiddleware(database))
 		r.Get("/", handleListBlocks(svc))
-		r.Put("/{userId}", handleBlockUser(svc))
+		r.Put("/{userId}", handleBlockUser(svc, broadcaster))
 		r.Delete("/{userId}", handleUnblockUser(svc))
 	})
 }
@@ -381,7 +381,7 @@ func handleRenameGroupDM(svc *service.Services, broadcaster DMBroadcaster) http.
 }
 
 // handleBlockUser blocks a user.
-func handleBlockUser(svc *service.Services) http.HandlerFunc {
+func handleBlockUser(svc *service.Services, broadcaster DMBroadcaster) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		user, _ := r.Context().Value(UserKey).(*db.User)
 		if user == nil {
@@ -398,6 +398,23 @@ func handleBlockUser(svc *service.Services) http.HandlerFunc {
 			writeServiceError(r.Context(), w, err)
 			return
 		}
+
+		// Revocation must evict a live session, not merely block the next
+		// join (the same invariant the voice sweep states): without this, a
+		// blocked user already in the pair's 1:1 DM voice call stays in it
+		// indefinitely — the block gate otherwise runs only on voice_join and
+		// voluntary voice_token_refresh, both of which the blocked client
+		// controls. Group DM calls are deliberately untouched, matching
+		// requireDMNotBlocked's group exemption.
+		if ve, evictable := broadcaster.(dmVoiceEvictor); evictable {
+			if chID, exists, err := svc.DMs.SharedOneToOneDM(r.Context(), user.ID, targetID); err != nil {
+				slog.Warn("block: shared-DM lookup for voice eviction failed",
+					"blocker_id", user.ID, "target_id", targetID, "err", err)
+			} else if exists {
+				ve.DisconnectFromVoiceInChannel(context.WithoutCancel(r.Context()), targetID, chID)
+			}
+		}
+
 		writeJSON(w, http.StatusOK, map[string]string{"message": "user blocked"})
 	}
 }