fix: isolate sentinel-constant test + disable js-lint

Two CI failures fixed:

1. PHPUnit constant-scoping bleed: test_p0_executor_path_sentinel_key_does_not_
   leak defines PRV_OPENROUTER_API_KEY as a process-scoped PHP constant.
   Running after CaptureWriter (alphabetically earlier), KeyStoreTest's
   resolver tests saw the canary value instead of empty/option.
   Fix: @runInSeparateProcess + @preserveGlobalState disabled so the
   constant is confined to its own forked PHP process.

2. JS lint job failure: has_js: true caused the reusable CI's lint-js job
   to attempt npm ci, but pr-vision has no package.json.
   Fixed: has_js: false.

Agent-Session: claude/adopt-ci-20260616

.github/workflows/ci.yml

@@ -17,6 +17,6 @@ jobs:
     uses: peptiderepo/peptide-e2e/.github/workflows/ci.yml@main
     with:
       tests: stubs
-      has_js: true
+      has_js: false
       line_limit_paths: includes
     secrets: inherit