fix(pregate): waive version-stamp-only manifests from the lanes check (GBRA-95) (#3461)

gbrain's release:restamp rewrites its plugin manifests and VERSION; its
base's .gstack/pregate.json declares no lane for them, and pregate reads
policy from the base, so every restamp PR failed lanes with
PREGATE_NO_LANE and could not fix itself (gbrain PRs 7625 and 7606).

lib/pregate/stamp-only.ts defines version-stamp-only per file kind: a JSON
document of the same shape whose every changed leaf is a bare version under
a key named for a version; plist <string> versions under a ...Version...
key; a VERSION file that is one bare version on both sides. lane-selection
applies it only after the import graph, the declarations, the regen
registry and both empty lanes found nothing; lanes prints the waived files
on their own line and --explain the per-file verdict. Anything else (a
changed description, a new key, a dependency pin, an added or deleted
manifest) keeps its PREGATE_NO_LANE.

Tests: pure rows for every rule, and bin fixtures for a stamp-only PR
(passes), a manifest with a changed description (refused), a mixed diff
(stamped files waived, the orphan source file still refused, a mapped file
still runs its test) and an added/deleted manifest.

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

scripts/lib/windows-curation.ts

@@ -65,6 +65,7 @@ export const KNOWN_WINDOWS_INCOMPATIBLE: Array<{ file: string; reason: string }>
   { file: 'test/pregate-regate.test.ts', reason: 'its REGATE and MIGRATION_COLLISION verdicts differ on windows-latest, not diagnosed in fix wave PR 5; gstack-pregate regate itself launches through lib/script-invocation.ts' },
   { file: 'test/pregate-invalidation.test.ts', reason: 'expects the Linux-host lanes verdict (the windows lane as the requires-remote obligation); on Windows the Linux lane is the obligation instead; gstack-pregate itself launches through lib/script-invocation.ts' },
   { file: 'test/pregate-selection.test.ts', reason: 'its gstack-pregate (bin) cases expect the Linux-host lanes verdict (a local lane run); on Windows the fixture\'s Linux lane is a requires-remote obligation' },
+  { file: 'test/pregate-stamp-only.test.ts', reason: 'its gstack-pregate (bin) cases expect the Linux-host lanes verdict for the mapped-file and test-reads-manifest fixtures, and its mode-change case needs a POSIX exec bit and symlink; the stamp rule it drives is POSIX-run like the other pregate fixtures' },
   { file: 'test/pregate-bats-nested.test.ts', reason: 'expects the bats lane to run locally, which it does on a Linux host; on Windows the fixture\'s Linux lane is a requires-remote obligation' },
   { file: 'test/pregate-docs-lane-review.test.ts', reason: 'spawns bin/gstack-pregate through test/helpers/pregate-fixture.ts runBin (shebang via CreateProcess); the docs-lane selection rules it drives are POSIX-run like the other pregate fixtures' },
   { file: 'test/pregate-dart.test.ts', reason: 'its dart, flutter and fvm stand-ins are bash scripts on a colon-joined PATH, which Bun.which and CreateProcess cannot use on Windows, and its containment case needs a POSIX symlink; the Dart lane code it drives is POSIX-run like the other pregate fixtures' },