Run platform-skipped Bake admission cases on Linux

Context

The complete pinned Bake corpus now runs through Home on macOS at Bun SHA 4982b91e3702094330f3be3883354c52b8c01323: 177 passed, 2 todo, 0 failed across 179 tests in 24 files. The two TODOs are upstream platform exclusions rather than observed Home failures:

1. test/bake/dev/hot.test.ts: hmr forwards every merged inotify sub-path from a directory batch is skipped on darwin and win32 because it specifically exercises Linux inotify merged-name batches.
2. test/bake/dev/bundle.test.ts: barrel optimization: two import statements from the same barrel (#28886) is skipped on darwin because upstream marks it flaky there and relies on Linux/Windows/Alpine coverage.

Tracked by #555 and #66.

Scope

• Run both unchanged tests through Home on a Linux host using the exact pinned Bun sources.
• Preserve the original assertions, workloads, and deadlines.
• Fix any Home-specific failure exposed by that run; if both pass unchanged, record the environment and evidence.
• Add or extend a Linux CI admission gate so these cases do not remain unmeasured TODOs.

Acceptance criteria

• Both platform-excluded tests execute as real tests (not TODO/skip) on Linux and pass through Home.
• Pinned source integrity is verified against 4982b91e3702094330f3be3883354c52b8c01323.
• #555 and #66 are updated with the resulting zero-TODO Bake count.

The reproducible Bake runner landed in 972979e09. On macOS it produces the expected 177 pass, 2 todo, 0 fail across all 24 files; the two TODOs are exactly the Linux admission cases tracked here. The next step is to run this same command in Linux CI and require both cases as real passes, bringing the Bake result to zero TODO.