ci: add markdown, website, and image lint checks

[vdusek]

Adds Markdown, website, and image lint checks to CI, mirroring the setup in apify-docs and apify-core. The docs and website now go through the same kind of automated checks as the Python code.

The website tooling moves from eslint + prettier (which weren't wired into CI) to oxlint and oxfmt, and markdownlint now covers the Markdown files.

Three jobs run in the existing Checks workflow:

• Markdown lint — markdownlint over README.md, CONTRIBUTING.md, and the docs/ folder.
• Website lint and format — oxlint plus an oxfmt --check formatting gate for the Docusaurus site.
• Image lint — fails when a PR adds unoptimized raster images, which should be converted with pnpm opt:images first.

Notes:

• The website JS keeps single quotes, set via .editorconfig (quote_type) and .oxfmtrc.json (singleQuote).
• The markdownlint config matches apify-docs: line length is disabled and inline HTML is allowed.
• Minor doc and code fixes were applied where needed to pass the new checks.

Closes #594

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.50%. Comparing base (4360695) to head (bb26fd1).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #882      +/-   ##
==========================================
- Coverage   94.52%   94.50%   -0.02%     
==========================================
  Files          48       48              
  Lines        5079     5079              
==========================================
- Hits         4801     4800       -1     
- Misses        278      279       +1     

Flag	Coverage Δ
integration	92.59% <ø> (-0.32%)	⬇️
unit	83.30% <ø> (ø)

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[Copilot]

Pull request overview

This PR extends the repository’s CI “Checks” workflow with documentation- and website-focused linting, aligning the repo with the tooling approach used in related Apify projects (markdownlint for Markdown; oxlint/oxfmt for the Docusaurus site) and adds a guardrail to prevent committing unoptimized raster images.

Changes:

• Add CI jobs for Markdown linting, website linting + formatting checks, and image optimization enforcement.
• Replace the website’s ESLint/Prettier setup with oxlint/oxfmt configuration and scripts.
• Adjust Markdown/docs formatting and add markdownlint configuration to satisfy lint rules.

Reviewed changes

Copilot reviewed 14 out of 19 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
.github/workflows/_checks.yaml	Adds Markdown/website/image lint jobs and Node setup for these checks.
.markdownlint.yaml	Introduces markdownlint configuration tailored for docs/MDX (e.g., disables line-length).
.editorconfig	Adds an editor configuration option affecting quote style metadata.
.rules.md	Markdown formatting tweaks (code fence language + list indentation).
CONTRIBUTING.md	Documents how to run the new linting/formatting checks and image optimization locally.
README.md	Adjusts Markdown table formatting to satisfy linting rules.
docs/02_concepts/04_error_handling.mdx	Adjusts Markdown table formatting to satisfy linting rules.
docs/02_concepts/10_custom_http_clients.mdx	Adjusts Markdown table formatting to satisfy linting rules.
docs/02_concepts/11_timeouts.mdx	Adjusts Markdown table formatting to satisfy linting rules.
website/.eslintrc.json	Removes the previous ESLint configuration.
website/.oxfmtrc.json	Adds oxfmt configuration (print width + ignore patterns).
website/docusaurus.config.js	Minor formatting changes (inline type-cast style).
website/oxlint.config.ts	Adds oxlint configuration using @apify/oxlint-config.
website/package.json	Adds markdownlint/oxlint/oxfmt scripts + dependencies; updates lint/format commands and adds image optimization script.
website/pnpm-lock.yaml	Updates lockfile to reflect the new lint/format toolchain dependencies.
website/src/plugins/docusaurus-plugin-segment/segment.js	Formatting changes consistent with the new formatter.
website/src/theme/DocItem/Content/index.js	Fixes a missing semicolon in a JSX return statement.
website/tools/docs-prettier.config.js	Removes the old Prettier config used for docs formatting.
website/tools/utils/externalLink.js	Updates Node URL import style and applies formatting changes.

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[Copilot]

Pull request overview

Copilot reviewed 14 out of 19 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 14 out of 19 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 16 out of 21 changed files in this pull request and generated no new comments.