docs(upstream): record catch-up decisions and refresh watched work

[rynfar]

Record the merged A1–A4 catch-up batch and its seven implementation PRs without advancing the full upstream review cursor. All 10 selected upstream commits and both Pylon release repairs merged with green checks after maintainer approval. A refresh through upstream b438447f67 leaves 455 unmatched, unselected commits for later assessment; this is not a missing-fix count. Preserve the earlier targeted September 4 record and consolidate the per-PR adaptations, final commit references, and verification here.

Refresh WATCH-1 after upstream closed #5760 and marked #8097 ready for review. Pylon #178 still owns the OpenCode task gap; #8097 remains unmerged and overlaps Pylon #137. Owner issue #114 is updated with this review state and the ledger PR link. DEF-8 remains due for the separate dev-loop/product split; DEF-7, WATCH-2, and WATCH-3 retain their November 1 revisit dates.

Validation: checked upstream issue/PR states, watched paths at f12d39359f, the Expo 57 merge, merged implementation PRs and commit references, formatting, and diff integrity. The merged code tree matches the combined branch that passed 342 focused tests, server typecheck, and release smoke.

Publication: Nightly .120 is live. The full release workflow passed, including both signed/notarized macOS builds, Windows, Linux, quality checks, and hosted web deployment. Verified the source tag, uploaded artifacts, updater manifests, and .120 in the public hosted JavaScript bundle. A final protected-upstream fetch still ends at b438447f67, so 455 remains the current assessment backlog.

Model: GPT-6 Astra. Harness: Codex.

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.6 KiB	13.6 KiB	+14 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.1 KiB	7.1 KiB	−1 B (−0.0%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.5 KiB	6.6 KiB	+15 B (+0.2%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	56.5 KiB	56.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	8	8	0 (0.0%)	21	✅
Claude	Total thread wire	13.8 KiB	13.7 KiB	−135 B (−1.0%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.1 KiB	7.1 KiB	−2 B (−0.0%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.7 KiB	6.6 KiB	−133 B (−1.9%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	58.2 KiB	57.3 KiB	−884 B (−1.5%)	66.4 KiB	✅
Claude	Live turn messages	9	8	−1 (−11.1%)	21	✅

Baseline: 9a4b541 · PR result: 26e4a77 · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 111.2 KiB
• Claude decoded thread snapshot: 111.9 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.