Keep git fatal stderr off the TUI and teach /yolo

[TheGreatAxios]

Summary

• Git worktree listing and environment probes discard stderr, so a folder that is not a checkout no longer paints fatal: not a git repository through the TUI
• Idle landing shows /yolo as a second door, and the permission overlay names /yolo skip prompts

Brian Fox hit both on first run: git fatal over the permission prompt, and no discoverable skip-permissions path.

Verification

• bun run typecheck and bun run build pass
• Focused tests for the changed files pass (worktree-roots, environment, landing, overlays)

Fixes CL-7290
Fixes CL-7289

[linear-code]

CL-7290

CL-7289

[TheGreatAxios]

Critic · Comment

Git probes discard stderr; /yolo is named on landing and the permissions overlay only.

Findings

• src/agent/environment.test.ts — async “no git fatal” tests spy process.stderr.write, which does not observe inherited fd 2. Sync listWorktreeRootsSync is a real detector for the original execFileSync leak. Not blocking: production stdio already ignores stderr.

Notes

• Focused tests on the changed files: 58 pass. bun run typecheck exits 0.

[TheGreatAxios]

Greybeard · Comment

Stderr is silenced at the git subprocess, not the renderer. Permissions-overlay /yolo is the right ask-time layer.

Findings

• src/agent/environment.ts — hand-rolled spawn is extra. Async execFile already pipes stderr. The load-bearing fix is listWorktreeRootsSync with stdio: ["ignore", "pipe", "ignore"], same as src/session/project-key.ts.
• src/tui/landing.ts — a second idle door spends chrome on a sticky skip-permissions switch. Overlay hint is the friction-moment layer.

Notes

• Landing /yolo is the CL-7289 product ask (teach the escape hatch before the first prompt). Overlay stays either way.
• Spawn rewrite is being folded back to execFile + ignored stderr.

[TheGreatAxios]

Draper · Comment

Landing two-door and the permissions title compose at 80-col. Nothing critical.

Findings

• src/tui/landing.ts:84 — /yolo rest is 51 cols; MARK_SMALL is flush at 80-col (77/77). MARK_LARGE now needs 102 content cols (hero test moved 96 → 120).
• src/tui/shell.ts:1341 — admin permissions · Enter revokes plus the long hint overflows an 80-col interior and falls back to Esc · Enter · /yolo.

[TheGreatAxios]

Review · Comment

Git worktree listing and environment probes discard stderr; idle landing and the permissions overlay name /yolo.

No blocking findings. GitHub blocks self-approve on this PR.

Notes

• Landing /yolo is the CL-7289 product ask. Overlay hint stays at the ask.
• Greybeard spawn rewrite is folded: probes use execFile/execFileSync with ignored stderr, matching project-key.ts.
• Async stderr tests still spy process.stderr.write; the load-bearing detector is listWorktreeRootsSync.