fix(ci): main passes the fork stack and unused-code checks again

[lukemaj]

What: main passes the Fork Stack Model and Check (knip) jobs again.
Why: #70 and #77 edited upstream files (AGENTS.md, ThreadPullRequestsPanel.tsx, t3.json) without allowlisting them, and #76 exported LINKED_ISSUE_STATES_REFRESH_MS, which nothing imports.
So what: Merges once CI is green; no follow-up needed.

Changes

• scripts/fork-upstream-edits.txt and docs/fork-features.md: t3.json -> branding, AGENTS.md -> fork-maintenance, ThreadPullRequestsPanel.tsx -> issues-links.
• apps/web/src/state/issues.ts: the constant is no longer exported.

Proof

• bash scripts/fork-check.sh: fork-features: OK (18 features). fork-check: OK.
• knip runs in CI.

Elon record

• Requirements and who asked: The user asked to fix and merge fix(web): Chromeria mark is readable in the sidebar; project icon is Chromeria #77; its CI showed these two failures.
• Deleted: An export nothing imports.
• Bottleneck: Allowlist entries missing for three files.
• Checked myself: Read both failing job logs and ran fork-check locally.

Model: Claude Opus 5.5, Claude Code in T3 Code.

🤖 Generated with Claude Code

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

ℹ️ The exact PR base did not have a successful artifact. Baseline uses the latest successful main measurement shown below.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.5 KiB	13.5 KiB	+3 B (+0.0%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.1 KiB	7.1 KiB	+9 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.4 KiB	6.4 KiB	−6 B (−0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	56.2 KiB	56.2 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	9	9	0 (0.0%)	21	✅
Claude	Total thread wire	13.5 KiB	13.5 KiB	+30 B (+0.2%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.1 KiB	7.1 KiB	−5 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.4 KiB	6.4 KiB	+35 B (+0.5%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	+44 B (+0.1%)	66.4 KiB	✅
Claude	Live turn messages	8	9	+1 (+12.5%)	21	✅

Baseline: f8a22e9 · PR result: bec20a5 · 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: 113.9 KiB
• Claude decoded thread snapshot: 114.6 KiB

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