feat(validator): infer the context type in validation func

[yusukebe]

The author should do the following, if applicable

• Add tests
• Run tests
• bun run format:fix && bun run lint:fix to format the code
• Add TSDoc/JSDoc to document the code

[github-actions]

Bundle size check

	main (b06005a)	#4554 (384d9d5)	+/-
Bundle Size (B)	18,363B	18,363B	0B
Bundle Size (KB)	17.93K	17.93K	0K

Compiler Diagnostics (tsc)

	main (b06005a)	#4554 (384d9d5)	+/-
Files	303	303	0
Lines	140,900	140,900	0
Identifiers	128,526	128,526	0
Symbols	269,140	269,140	0
Types	198,856	198,856	0
Instantiations	639,355	639,355	0
Memory used	363,703K	360,892K	-2,811K
I/O read	0.02s	0.03s	0.01s
I/O write	0s	0s	0s
Parse time	0.72s	0.84s	0.12s
Bind time	0.29s	0.35s	0.06s
Check time	2.81s	3.2s	0.39s
Emit time	0s	0s	0s
Total time	3.81s	4.4s	0.59s

Compiler Diagnostics (typescript-go)

	main (b06005a)	#4554 (384d9d5)	+/-
Files	272	272	0
Lines	118,789	118,789	0
Identifiers	117,959	117,959	0
Symbols	378,470	378,470	0
Types	360,479	360,479	0
Instantiations	3,764,726	3,764,726	0
Memory used	250,866K	250,935K	69K
Memory allocs	10,583,127	10,583,088	-39
Parse time	0.077s	0.087s	0.01s
Bind time	0.017s	0.022s	0.005s
Check time	1.5s	1.52s	0.02s
Emit time	0s	0s	0s
Total time	1.596s	1.631s	0.035s

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Reported by octocov

[github-actions]

HTTP Performance Benchmark

Framework	Runtime	Average	Ping	Query	Body
hono (origin/main)	bun	37,079.35	51,695.97	33,222.81	26,319.28
hono (current)	bun	36,990.46	51,414.54	33,093.53	26,463.32
Change		-0.24%	-0.54%	-0.39%	+0.55%