Add structured CI phase and fixture telemetry

[PraneethMerugu]

Summary

• record cache observation, instantiate, explicit precompile, import, and suite phases as non-gating JSONL for every LocalMath qualification profile
• retain raw ParallelTestRunner logs and publish structured fixture totals for initialization, compile/execution share, GC, allocation, RSS, worker identity, and fixtures over 50 seconds
• collect opt-in per-fixture TOML timing for package, scientific, and Metal witnesses, including the first Metal execution family, without changing test selection or grouping
• upload telemetry from PR, main, Metal, macOS, scientific, and documentation jobs using a commit-pinned artifact action

Validation

• complete package suite through telemetry wrapper: 1,943/1,943 assertions passed across 46 fixtures (2 workers)
• structured parser recovered all 46 fixtures and individually marked the three fixtures above 50 seconds
• focused end-to-end package telemetry: test_public_api, 27/27 passed, raw log + phase JSONL + fixture TOML + structured totals generated
• Python byte-compilation, Ruby YAML parse, Julia parse of all changed runners, and git diff --check passed
• scientific telemetry run was started but intentionally stopped after bounded validation to publish for hosted qualification; hosted scientific/Metal remain authoritative

No timing value is a pass/fail threshold, and cache restoration remains infrastructure rather than correctness evidence.