docs: Fix links to vision

[Xuanwo]

Which issue does this PR close?

Closes #.

Rationale for this change

As title.

What changes are included in this PR?

Are there any user-facing changes?

[codspeed-hq]

CodSpeed Performance Report

Merging #5466 will degrade performances by 15.89%

_{Comparing docs (8c70543) with main (6ccef00)}

Summary

⚡ 8 improvements
❌ 4 regressions
✅ 61 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	docs	Change
❌	buffer 256 KiB * 32 chunk	154.4 ns	183.6 ns	-15.89%
❌	buffer 256 KiB * 4 chunk	154.4 ns	183.6 ns	-15.89%
❌	buffer 4.00 MiB * 32 chunk	154.4 ns	183.6 ns	-15.89%
❌	buffer 4.00 MiB * 4 chunk	154.4 ns	183.6 ns	-15.89%
⚡	256 KiB * 1000k chunk	183.6 ns	154.4 ns	+18.88%
⚡	256 KiB * 1000k truncate	245.8 ns	216.7 ns	+13.46%
⚡	256 KiB * 100k chunk	183.6 ns	154.4 ns	+18.88%
⚡	256 KiB * 100k truncate	245.8 ns	216.7 ns	+13.46%
⚡	256 KiB * 10k chunk	183.6 ns	154.4 ns	+18.88%
⚡	256 KiB * 10k truncate	245.8 ns	216.7 ns	+13.46%
⚡	256 KiB * 1k chunk	212.8 ns	183.6 ns	+15.89%
⚡	256 KiB * 1k truncate	245.8 ns	216.7 ns	+13.46%

[Xuanwo]

Thank you @PsiACE for the review!

[tisonkun]

You can actually make a redirect from / to /docs.

I suppose all other links to /docs will be broken now.