merge: integrate origin/main (406 commits) into live branch

Merge upstream's paired-room stabilization, dedicated message-runtime-loop,
outbound delivery refactor (ipc-outbound-delivery / deliverFormattedCanonicalMessage),
discord module split, dashboard rework, and migrations 015-018 into our branch.

Conflict policy: prefer upstream for the heavily-refactored paired-room /
message-runtime / db cluster (it supersedes our earlier loop band-aids), keep
only orthogonal unique fixes:
- codex bundled-JS launcher fix (codex-warmup.ts)
- slot-aligned Claude+Codex usage primer (usage-primer.ts) re-wired into index.ts
- MemoryHigh=3G cgroup bound, discord perms diagnostic, prompt docs
- progress null-race + silent-failure publish guards (message-turn-controller.ts)

Dropped (superseded by upstream or unwired): reviewer STEP_DONE/TASK_DONE loop
band-aids, router markdown-escape override, register tribunal-default+git-init,
restart-context rewindToSeq (unwired).

Verified: typecheck clean, build clean, vitest shows zero new regressions vs the
origin/main baseline (only pre-existing env-config failures remain).

src/codex-usage-collector.ts

@@ -300,13 +300,9 @@ export function applyCodexUsageToAccount(
 
   // Select the effective bucket
   const primaryBucket = usage.find((l) => l.limitId === 'codex');
-  let effective: CodexRateLimit | null = null;
+  const effective = primaryBucket ?? (usage.length === 1 ? usage[0] : null);
 
-  if (primaryBucket) {
-    effective = primaryBucket;
-  } else if (usage.length === 1) {
-    effective = usage[0];
-  } else {
+  if (!effective) {
     // Multiple unknown buckets — cannot determine which is authoritative
     logger.warn(
       { account: accountIndex + 1 },