chore: fix cascading reparses in the lazy-input example

[hardfist]

Mark ParsedFile::value and ParsedFile::links as #[tracked] so changing a leaf input no longer changes parent identities and triggers cascading reparses.

This completes the lazy-input example's migration to coarse-grained tracked structs introduced in #657.

[netlify]

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[codspeed-hq]

Merging this PR will improve performance by 30.87%

⚡ 1 improved benchmark
✅ 73 untouched benchmarks
⏩ 1 skipped benchmark¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	WallTime	parallel_fast_path[NoEviction]	472.7 µs	361.2 µs	+30.87%

Tip

Curious why this is faster? Comment @codspeedbot explain why this is faster on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing hardfist:agent/fix-lazy-input-tracked-fields (1e91509) with master (a79c456)}

Footnotes

1. 1 benchmark was skipped, so the baseline result was used instead. If it was deleted from the codebase, click here and archive it to remove it from the performance reports. ↩