chore(ci): improve rules_check task

[Sec-ant]

Summary

• Discard BlockType and use DocumentFileSource as the single source of truth.
• Retain the code block tag from the input instead of regenerating it.
• Use code-block.{js,css,json...} as the file path displayed in code block diagnostics.

I will apply the same modifications to the codegen task in the website repo after this is merged.

Test Plan

CI should pass.

[Sec-ant]

We should be more forgiving here, in case we want to add some foreign code blocks (like shell) for illustration purpose.

[github-actions]

Parser conformance results on

js/262

Test result	main count	This PR count	Difference
Total	50787	50787	0
Passed	49680	49680	0
Failed	1107	1107	0
Panics	0	0	0
Coverage	97.82%	97.82%	0.00%

jsx/babel

Test result	main count	This PR count	Difference
Total	40	40	0
Passed	37	37	0
Failed	3	3	0
Panics	0	0	0
Coverage	92.50%	92.50%	0.00%

symbols/microsoft

Test result	main count	This PR count	Difference
Total	6534	6534	0
Passed	2087	2087	0
Failed	4447	4447	0
Panics	0	0	0
Coverage	31.94%	31.94%	0.00%

ts/babel

Test result	main count	This PR count	Difference
Total	669	669	0
Passed	597	597	0
Failed	72	72	0
Panics	0	0	0
Coverage	89.24%	89.24%	0.00%

ts/microsoft

Test result	main count	This PR count	Difference
Total	18217	18217	0
Passed	13961	13961	0
Failed	4256	4256	0
Panics	0	0	0
Coverage	76.64%	76.64%	0.00%

[codspeed-hq]

CodSpeed Performance Report

Merging #3165 will not alter performance

_{Comparing ci/rule-check (7f65f5d) with main (5d76e45)}

Summary

✅ 92 untouched benchmarks