Migrate Core Patches to TypeScript

[yihao03]

What is the purpose of this pull request?

• Documentation update
• Bug fix
• Feature addition or enhancement
• Code maintenance
• DevOps
• Improve developer experience
• Others, please explain:

Overview of changes:
Migrated nunjucks, htmlparser2 and markdown-it patches to TypeScript and ESM.

Anything you'd like to highlight/discuss:
As these patches are modifying the internals of the npm packages, the types
we worked on are not exposed in the @types packages. We have to do module augmentation
to add the types that we are patching. Considering that the packages haven't been updated
in a while and will likely not be updated in the near future, we are fine with this approach.

Testing instructions:
Pull this branch and run npm run setup to make sure exisitng .js files are cleaned
and .ts files are compiled. Then run npm test to make sure all tests are passing.

Proposed commit message: (wrap lines at 72 characters)
Migrated nunjucks, htmlparser2 and markdown-it patches to TypeScript and ESM.

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Checklist: ☑️

• Updated the documentation for feature additions and enhancements
• Added tests for bug fixes or features
• Linked all related issues
• No unrelated changes

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Reviewer checklist:

Indicate the SEMVER impact of the PR:

• Major (when you make incompatible API changes)
• Minor (when you add functionality in a backward compatible manner)
• Patch (when you make backward compatible bug fixes)

At the end of the review, please label the PR with the appropriate label: r.Major, r.Minor, r.Patch.

Breaking change release note preparation (if applicable):

• To be included in the release note for any feature that is made obsolete/breaking

Give a brief explanation note about:

• what was the old feature that was made obsolete
• any replacement feature (if any), and
• how the author should modify his website to migrate from the old feature to the replacement feature (if possible).

[codecov]

Codecov Report

❌ Patch coverage is 76.14679% with 26 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.89%. Comparing base (5a90880) to head (ea62ea3).

Files with missing lines	Patch %	Lines
...re/src/patches/nunjucks/context-overrides-frame.ts	57.14%	24 Missing ⚠️
packages/core/src/patches/nunjucks/load-event.ts	81.81%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2853      +/-   ##
==========================================
- Coverage   71.92%   71.89%   -0.03%     
==========================================
  Files         132      132              
  Lines        7358     7359       +1     
  Branches     1516     1637     +121     
==========================================
- Hits         5292     5291       -1     
- Misses       2021     2062      +41     
+ Partials       45        6      -39     

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[Copilot]

Pull request overview

This PR migrates MarkBind’s internal “core patches” (monkey-patches applied to nunjucks, htmlparser2, and a markdown-it custom-component patch set) from CommonJS .js files to TypeScript sources, and adds local .d.ts files to type internal/unstable APIs that aren’t covered by upstream @types/* packages.

Changes:

• Converted patch entrypoints from *.js to *.ts and updated exports/imports accordingly.
• Added manual TypeScript declaration files for patched/hidden internals (nunjucks submodules + internals, htmlparser2 internals).
• Updated ignore lists to avoid committing compiled patch outputs while still tracking the “manual” declaration files.

Reviewed changes

Copilot reviewed 13 out of 17 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/core/src/patches/nunjucks/nunjucks-submodules.d.ts	Adds ambient module declarations for untyped nunjucks internal submodules.
packages/core/src/patches/nunjucks/nunjucks-internals.d.ts	Adds module augmentations for nunjucks internals used by MarkBind patches.
packages/core/src/patches/nunjucks/load-event.ts	Migrates the nunjucks “load event” patch to TS + ES imports.
packages/core/src/patches/nunjucks/index.ts	TS patch entrypoint (side-effect imports).
packages/core/src/patches/nunjucks/index.js	Removes old CommonJS entrypoint.
packages/core/src/patches/nunjucks/context-overrides-frame.ts	Migrates and types the MarkBind context/frame priority patch.
packages/core/src/patches/index.ts	Migrates patch aggregator to TS and wires ignore-tag injections.
packages/core/src/patches/index.js	Removes old CommonJS patch aggregator.
packages/core/src/patches/htmlparser2.ts	Migrates htmlparser2 patch to TS + ES imports and exports.
packages/core/src/patches/htmlparser2-internal.d.ts	Adds declaration augmentation for htmlparser2 internals used by the patch.
packages/core/src/lib/markdown-it/patches/custom-component/inlineTags.ts	Converts export style to TS-friendly export =.
packages/core/src/lib/markdown-it/patches/custom-component/htmlRe.ts	Converts to named ESM exports.
packages/core/src/lib/markdown-it/patches/custom-component/htmlInlineRule.ts	Migrates to TS imports/exports and adds types.
packages/core/src/lib/markdown-it/patches/custom-component/htmlBlockRule.ts	Migrates to TS imports/exports and adds types.
packages/core/src/lib/markdown-it/patches/custom-component/customComponentPlugin.ts	Migrates plugin wiring to TS imports/exports and adds types.
.gitignore	Ignores compiled patch JS outputs; attempts to unignore manual .d.ts files.
.eslintignore	Ignores compiled patch JS outputs for linting.

Comments suppressed due to low confidence (3)

packages/core/src/patches/htmlparser2.ts:465

• injectIgnoreTags is typed as string[], but the caller path (PluginManager -> patches.ignoreTags) passes a Set of tags. Since the implementation only spreads the input, it can support any iterable; consider changing the parameter type to Iterable<string> (or readonly string[]) and converting to an array before spreading if needed.
  packages/core/src/lib/markdown-it/patches/custom-component/customComponentPlugin.ts:41
• injectTags is typed as tagsToIgnore: string[], but the upstream call path (PluginManager -> patches.ignoreTags) passes a Set of tags. Consider widening this (and the customComponentPlugin parameter) to Iterable<string> / ReadonlySet<string> | readonly string[] so the existing call-site type-checks without forcing an array conversion.
  packages/core/src/lib/markdown-it/patches/custom-component/htmlBlockRule.ts:6
• initCustomComponentHtmlBlockRule is typed to take string[], but the surrounding logic (Array.from(tagsToIgnore)) works with any iterable and the upstream caller provides a Set of tags. Widening this parameter to Iterable<string> (or accepting Set<string> | string[]) would align with actual usage and avoid type errors once the caller is updated.

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[Copilot]

ignoreTags is typed to accept string[], but its only caller (PluginManager._collectPluginTagConfigs) passes a Set of tag names. This will fail type-checking and also forces downstream helpers (injectIgnoreTags / injectTags) to accept only arrays even though they work fine with iterables. Consider widening the parameter type to Iterable<string> (or Set<string> | string[]) and updating the injected functions’ signatures accordingly.

Suggested change

	function ignoreTags(tagsToIgnore: string[]) {
	function ignoreTags(tagsToIgnore: Iterable<string>) {