chore(upstream-sync): advance lastSyncedTag v2026.824.1 -> v2026.831.1

[claudegoogl-sudo]

Thinking Path

• The v2026.831.1 upstream sync landed on master via sync(upstream): merge upstream release v2026.831.1 into fork master #322 (merge commit 62b44d5ae, verified reachable from master; 21/21 checks green).
• The upstream-sync routine never auto-advances after an escalated tag; the durable cursor .paperclip/upstream-sync.json must be advanced by an explicit bookkeeping commit (established pattern: the v2026.707.0 -> v2026.824.1 reconcile).
• Without this advance, the next weekly tick re-processes an already-landed release.

What Changed

• .paperclip/upstream-sync.json: lastSyncedTag v2026.824.1 -> v2026.831.1, lastSyncedSha pinned to the upstream tag commit 65ec059bde30… (marker convention), fresh etag from releases/latest, pendingPrUrl: null, _syncNote documenting the landing chain (sync(upstream): merge upstream release v2026.831.1 into fork master (CI-fix round 5) #320 -> sync(upstream): merge upstream release v2026.831.1 into fork master #321 -> sync(upstream): merge upstream release v2026.831.1 into fork master #322, updateBranch outage, ruleset constraints, the one-line CI fix).

Verification

• Upstream tag v2026.831.1 verified ancestor of current master (git merge-base --is-ancestor).
• JSON shape validated against the schema in skills/upstream-sync/SKILL.md (all required fields present).
• No content changes outside the state file.

Risks

• None beyond bookkeeping: pure cursor metadata; a bad value would only make the next tick no-op or re-escalate visibly.

Model Used

Claude Sonnet 4.5 (claude-sonnet-4-5), via Paperclip CTO agent (prime_local adapter), extended reasoning + tool use.

Checklist

• One logical change (cursor advance only)
• No unrelated cleanups bundled
• No internal ids/links beyond same-repo PR references
• State file shape matches the routine's schema