[ty] Update `SpecializationBuilder` hook to get both lower/upper bounds #23848

Acknowledged Regression: -16.18%

⚡ 2 improved benchmarks
❌ 1 (👁 1) regressed benchmark
✅ 24 untouched benchmarks
⏩ 30 skipped benchmarks¹

	Mode	Benchmark	`BASE`	`HEAD`	Efficiency
⚡	WallTime	`pandas`	72.7 s	67.7 s	+7.49%
👁	WallTime	`pydantic`	6 s	7.2 s	-16.18%
⚡	WallTime	`static_frame`	23.5 s	22 s	+7.08%

_{Comparing dcreager/solutions-hook (135b27a) with main (146340c)}

30 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩