perf: avoid type checks in memo and field lookups

[MichaReiser]

Memo and field lookups repeated TypeId checks even though the database-bound ingredient fixes the accessed type. Bind each ingredient to its database context and acquire thread-local state only for operations that need it.

Fixed hot memo hits drop from 233 to 228 instructions (-2.15%), untracked tracked-struct field bodies drop from 59 to 58, CodSpeed reports a 6.76% aggregate improvement, and ty's 29-case suite improves by 0.145% weighted overall.

Testing: Full target, manual-registration, lint, and performance suites passed.

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[codspeed-hq]

Merging this PR will degrade performance by 9.6%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

❌ 5 regressed benchmarks
✅ 69 untouched benchmarks
⏩ 1 skipped benchmark¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	WallTime	parallel_fast_path[NoEviction]	361.3 µs	419.9 µs	-13.96%
❌	WallTime	project_check_then_incremental[NoEviction]	6.1 ms	6.8 ms	-11.11%
❌	WallTime	parallel_fast_path[Lru]	3.8 ms	4.2 ms	-9.87%
❌	WallTime	project_check_then_incremental[Lru]	10 ms	10.9 ms	-8.75%
❌	WallTime	scan_resistance[NoEviction]	836.8 µs	872 µs	-4.03%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing MichaReiser:optimize-memo-lookup (1ff4965) with master (25ed9d3)}

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. ↩

[MichaReiser]

This is cool but I don't think codex's reasoning here is safe. The issue is that zalsa could be smuggled in. So we'd have to make fetch unsafe.