Add scoped retirement performance matrix

[Zetazzz]

Scope

Focused fresh-process performance harness for the two preceding stacked PRs. It continues to use Graphile default presets directly and does not load ConstructivePreset or unrelated CNC application plugins.

The only architecture compatibility change in this update is that retire arms now import the CNC-owned BuildStateRetirementPlugin from the narrow graphile-settings/plugins/build-state-retirement module instead of importing a plugin from patched graphile-build.

Matrix

arm	scoped introspection	build-state retirement
stock	no	no
scoped	yes	no
retire	no	yes
scoped-retire	yes	yes

The harness retains fresh-process isolation, schema/query verification, lifecycle validation, deterministic scheduling, JSON output, and database URL redaction.

Validation

• unit tests: 8 passed across 4 suites
• CJS and ESM build: passed
• ESLint on compatibility change: passed
• frozen-lockfile install: passed
• real PostgreSQL four-arm smoke: passed
  • four unique worker PIDs: 46292, 46293, 46294, 46295
  • one schema hash across all arms: 3b9dab5243611a57da1c0721ea3bc1aba455051124e43549e3c326178b3e97c1
  • stock/scoped retained; retire/scoped-retire released
  • validation had no errors
  • JSON contained no database URL

[Zetazzz]

Closing as superseded by the reusable harness in #1716 and the optimization-specific suites in #1719 and #1722. The fixed matrix and its validation history remain available here for reference.