chore(upstream): adopt the 2026-08-19 T3 Code batch

[rynfar]

Adopts 20 of 22 upstream commits from 82b8a938..2aa5f095 as ten change sets. git cherry reported every one absent from Pylon, so nothing was patch-equivalent, and the deferred register was empty going in.

The most valuable change is #7459, which stops probing Grok and OpenCode unless they are turned on and fixes an envelope-vs-config enabled conflict most-restrictively so a user's explicit disable is never silently undone. Two pairs had to be taken in order: #7473/#7477 (the second deletes macArch.ts and supersedes the first) and #7445/#7460 (the second exempts cold start from throttling the first introduced).

Skipped, both deliberately:

• #7421 (AUR launcher icons) — Pylon has no packaging/aur directory.
• #6563 (npx t3 triage) — its playbook hardcodes pingdotgg/t3code, searches T3's issues, and builds a github.com/pingdotgg/t3code/issues/new URL, so adopting it as-is would funnel Pylon users' bug reports into T3's tracker. Held for a from-scratch Pylon implementation, which needs a product decision first: pylon-code/pylon is private, so there is no public tracker for a generated issue to land in.

Conflicts were resolved Pylon-first. ThreadCommandSubtitle.tsx kept Pylon's simplified WorkspaceIcon and dropped upstream's design-review variant toggle while adopting the renames the new palette imports. ChatComposer.tsx has diverged structurally (4240 lines vs upstream's 2824), so its two-line change was hand-ported. The launchd commit's three conflicts were all branding: upstream's platform-aware behavior kept, Pylon's copy kept.

Verification

• 617 tests across 21 changed test files, 0 failures. Worth knowing: vp test run globs nested worktrees under .prime/ and .claude/worktrees/, which have no node_modules, producing ~72 phantom failures while still exiting 0. Pass --exclude '**/.prime/**' --exclude '**/.claude/worktrees/**' for real signal.
• Typecheck clean across all 8 affected packages.
• Validated live in the web client against a seeded copy of real data: pairing, the new composer placeholder, Settings → Providers showing Cursor/Grok/OpenCode disabled with Pylon copy intact, and the command palette rendering the new project-location subtitle through the component that was hand-resolved.
• An xhigh review produced 13 findings. One confirmed and fixed here (see below); one dismissed as a documented upstream decision (Macs always get arm64 — the code comment says browsers cannot tell Apple Silicon from Intel and Intel users choose on /download); the rest are upstream design tradeoffs, adopted as-is rather than rewritten inside an adoption PR, and recorded in the ledger.

One fix on top

7d0a295db — the #7317 inherited-upstream guard returned without skipped, so the caller treated a deliberate non-lookup as an authoritative "no PR": it wiped the branch's cached PR and returned null instead of the fallback. The unpublished-branch guard immediately below sets that flag for exactly this reason, with a comment saying a skipped lookup means "we did not ask". Worth sending upstream.

Two things to decide later

• The launch agent label is com.t3tools.t3code.service. AGENTS.md forbids renaming compatibility identifiers during adoption, so it was kept — but Pylon and T3 Code are meant to coexist on one machine, and both would now claim the same launchd label and TCC records.
• #7459 is a one-way default flip with no migration. writeSettingsAtomically strips values equal to the default, so an install that had Grok on by matching the old default has nothing written for it and comes back disabled. That is the commit's intent, not a regression, but an explicit opt-in was indistinguishable from an untouched default.

Model: Claude Opus 5 in Pylon.

---

^{Need help on this PR? Tag @codesmith with what you need. Autofix is disabled.}