ci: run lint and performance contracts on hosted runners

[jonit-dev]

Lint and performance-contracts currently queue behind native and browser work on the three heavy local runners. In #416, performance-contracts waited 27m29 to execute for 41s. Recent successful hosted equivalents queued 2–3s and executed in 22–28s; those observations establish an available alternative, not a guaranteed critical-path saving.

Run only these two jobs on ubuntu-24.04 and update the existing hosted routing allowlist. Conditions, dependencies, commands, timeouts, candidate checkout identity and evidence remain unchanged. The prerequisite test job remains on its current route.

The light pool is not a safe substitution from current measurements: lint reached 1.94 GiB with little headroom under its 2 GiB cap, and performance-contracts reached 2.04 GiB. These are whole-job cgroup observations, including setup, rather than isolated command RSS.

Validation: existing routing contract failed before the workflow change and passed afterward; 301 CI structure, dependency, template selection and integration selection contracts passed. All 88 selected/instruction lint consumers passed after an ordinary isolated JS/DTS build; documentation links and agent mirrors passed. Whole-workspace lint exited 0 with existing warnings. Independent review confirmed the complete job blocks changed only runner values and found no actionable defects. Local work used reserved CPU cores and at most two test workers. No runner resource/security settings or active jobs were changed.

[jonit-dev]

Consolidated into #435 at verified published head 1015b95bc8f6aee51b60260d4ad8b1116cb2ccef per the requested single CI PR. The exact reviewed content from 22bdd34faec2b17f7503e9247d3bfef4a65ffac1 is present: hosted lint/performance-contracts routing and the matching allowlist expectations. Original body/checklist, immutable format patch/checksum, branch and CI receipts are preserved. #435 links this PR and owns normal required CI/review/merge queue qualification; no bypass or fast-PR qualification claim. Closing this superseded PR leaves its branch intact.