fix(ec-twoslash): improve code block processing

[Adammatthiesen]

This pull request enhances the codeblock processing for the expressive-code-twoslash package to improve the accuracy and reliability of Twoslash code block handling. The main focus is on ensuring that extra lines not present in the Twoslash output are removed, refining module resolution, and improving compatibility with ESLint and emitted code display.

Codeblock processing improvements:

• Improved the removal of extra lines from code blocks by iterating backwards and checking for line existence before deletion, ensuring no orphaned lines remain in the final output.

Module resolution and configuration:

• Refactored the way TSConfig paths and default library directories are resolved and used, clarifying variable naming and ensuring proper module resolution for Twoslash.

ESLint and emitted code handling:

• Adjusted the file extension logic so that when the trigger is "eslint", the code block receives a full filename with extension, improving ESLint's Twoslasher parsing and completions.
• Enhanced the update of code block language when displaying emitted code (e.g., via @showEmit), ensuring the output language matches the emitted result, which could be TypeScript, JavaScript, JSON, or .d.ts.

Documentation:

• Added a changeset documenting the patch, explaining that extra lines not present in the Twoslash output are now excluded from the final code block output.

[changeset-bot]

🦋 Changeset detected

Latest commit: 0b9a5f3

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
expressive-code-twoslash	Patch

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[htg-1-studiocms-cloud]

Dokploy Preview Deployment

Name	Status	Preview	Updated (UTC)
Expressive-Code-Twoslash Docs	✅ Done	Preview URL	2026-02-26T22:03:44.532Z

[pkg-pr-new]

css-js-gen

npm i https://pkg.pr.new/withstudiocms/expressive-code-twoslash/css-js-gen@91

expressive-code-twoslash

npm i https://pkg.pr.new/withstudiocms/expressive-code-twoslash@91

@ec-ts/twoslash

npm i https://pkg.pr.new/withstudiocms/expressive-code-twoslash/@ec-ts/twoslash@91

@ec-ts/twoslash-vue

npm i https://pkg.pr.new/withstudiocms/expressive-code-twoslash/@ec-ts/twoslash-vue@91

@ec-ts/vfs

npm i https://pkg.pr.new/withstudiocms/expressive-code-twoslash/@ec-ts/vfs@91

commit: 0b9a5f3

[apollo-git-bot]

Allure Report Summary

	Name	Duration	Stats	New	Flaky	Retry	Report
	css-js-gen Tests	11ms	37	37	0	0
	@ec-ts/twoslash Tests	29s 314ms	29	29	0	0
	@ec-ts/twoslash-vue Tests	6s 3ms	7	7	0	0
	@ec-ts/vfs Tests	9s 589ms	21	21	0	0