feat: add performance_analyze_file tool

[miyanaga]

This adds a new tool performance_analyze_file that lets you analyze trace files from the local filesystem.

Why

Currently, you can only analyze traces recorded live with performance_start_trace. But sometimes you already have trace files from Lighthouse, Chrome DevTools export, or other sources that you want to analyze.

What

• Added performance_analyze_file tool that takes a file path and parses the trace
• The analyzed trace is stored so you can use performance_analyze_insight to get details
• Added tests for success, file not found, and invalid JSON cases

Testing

npm run test

All tests pass.

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[miyanaga]

I have signed the CLA.

[OrKoN]

cc @natorion

[natorion]

I think this is useful as part of an automation.

I would suggest naming it performance_analyze_trace or something. Its a tracefile after all. I am not sure if we need it enabled/available per default though.

[OrKoN]

Thanks for the PR. Would you be open to integrate the logic into performance_start_trace (optional filepath argument) instead of creating a brand new tool?