Closes #29757
Closes #49387

This PR upgrades ESLint language server from `vscode-eslint 2.4.4` to
upstream `microsoft/vscode-eslint 3.0.24`, and make the workspace
configuration version-aware so ESLint 8, 9, and 10 take the correct
config-mode path.

The key part is that the 3.x bump alone is not enough. This PR keeps Zed
out of that path except where it is still actually needed. Rest
heavy-lifting is done by eslint server itself.

Zed now only overrides ESLint settings in the two known broken cases:
- ESLint 8.21-8.56 flat config: send `experimental.useFlatConfig = true`
  - ESLint 9 legacy config: send `useFlatConfig = false`
  
All other cases defer to `vscode-eslint 3.x`'s own config and
working-directory discovery.

For testing, I created https://github.com/smitbarmase/eslint-repros,
which contains a versioned ESLint repros covering root flat config,
legacy config, and package-local monorepo cases across ESLint 8, 9, and
10. Here is compare between `zed/main`, a pure `vscode-eslint 3.x`
upgrade and this branch with the config-mode fixes:

  ## zed main

  ```text
  eslint-v8_21-flat-root-single
  eslint-v8_56-flat-package-local-monorepo  -> breaks on main
  eslint-v8_56-flat-root-single
  eslint-v8_56-legacy-root-single
  eslint-v8_57-flat-package-local-monorepo  -> breaks on main
  eslint-v8_57-flat-root-single
  eslint-v8_57-legacy-root-single
  eslint-v9_0-flat-package-local-monorepo
  eslint-v9_0-flat-root-single
  eslint-v9_0-legacy-root-single            -> breaks on main
  eslint-v10_0-flat-package-local-monorepo
  eslint-v10_0-flat-root-single             -> breaks on main
  ```
  
  ## vscode-eslint 3.x upgrade

  ```text
  eslint-v8_21-flat-root-single
  eslint-v8_56-flat-package-local-monorepo  -> breaks on 3.x upgrade
  eslint-v8_56-flat-root-single
  eslint-v8_56-legacy-root-single
  eslint-v8_57-flat-package-local-monorepo
  eslint-v8_57-flat-root-single
  eslint-v8_57-legacy-root-single
  eslint-v9_0-flat-package-local-monorepo
  eslint-v9_0-flat-root-single
  eslint-v9_0-legacy-root-single            -> breaks on 3.x upgrade
  eslint-v10_0-flat-package-local-monorepo
  eslint-v10_0-flat-root-single             -> breaks on 3.x upgrade
  ```
  
  ## vscode-eslint 3.x upgrade + use flat config fixes

  ```text
  eslint-v8_21-flat-root-single
  eslint-v8_56-flat-package-local-monorepo
  eslint-v8_56-flat-root-single
  eslint-v8_56-legacy-root-single
  eslint-v8_57-flat-package-local-monorepo
  eslint-v8_57-flat-root-single
  eslint-v8_57-legacy-root-single
  eslint-v9_0-flat-package-local-monorepo
  eslint-v9_0-flat-root-single
  eslint-v9_0-legacy-root-single
  eslint-v10_0-flat-package-local-monorepo
  eslint-v10_0-flat-root-single
  ```
  
Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content is consistent with the [UI/UX
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

Release Notes:

- Fixed ESLint not reporting diagnostics in some cases for projects that
use flat-config, legacy-config, and monorepo projects across ESLint 8,
9, and 10.