[code-infra] Replace markdownlint-cli2 with eslint-plugin-mdx

[Janpot]

Mirrors mui/material-ui#48371. Drops markdownlint-cli2 in favor of remark-based linting via eslint-plugin-mdx, wired through @mui/internal-code-infra.

[pkg-pr-new]

• base-ui-tanstack-start

• vite-css-base-ui-example

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/react@4697
  

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/utils@4697
  

commit: f9594de

[code-infra-dashboard]

Bundle size

Bundle	Parsed size	Gzip size
@base-ui/react	0B(0.00%)	0B(0.00%)

Details of bundle changes

Performance

Total duration: 1,272.24 ms ▼-258.41 ms^(-16.9%) | Renders: 53 ⁽⁺⁰⁾ | Paint: 1,973.18 ms ▼-368.61 ms^(-15.7%)

Test	Duration	Renders
Checkbox mount (500 instances)	72.68 ms 🔺+2.75 ms(+3.9%)	1 (+0)
Tabs mount (200 instances)	231.16 ms ▼-84.07 ms(-26.7%)	4 (+0)
Menu mount (300 instances)	135.31 ms ▼-38.57 ms(-22.2%)	2 (+0)
Scroll Area mount (300 instances)	85.96 ms ▼-24.51 ms(-22.2%)	3 (+0)
Popover mount (300 instances)	100.52 ms ▼-22.43 ms(-18.2%)	2 (+0)

…and 7 more — details

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[LukasTy]

Looks good overall, very clean solution. 👍

However, is it expected that the runtime is ~4x slower (2min instead of 30s)?

I assume it's running on the whole codebase every time, whereas the previous solution probably ran only on the diff?

[Janpot]

However, is it expected that the runtime is ~4x slower (2min instead of 30s)?

I assume it's running on the whole codebase every time, whereas the previous solution probably ran only on the diff?

Likely the cache was busted. A rerun does it in 16s.

[LukasTy]

However, is it expected that the runtime is ~4x slower (2min instead of 30s)?
I assume it's running on the whole codebase every time, whereas the previous solution probably ran only on the diff?

Likely the cache was busted. A rerun does it in 16s.

Nice, then it's both cleaner and faster. 👏