feat: add TypeScript resolveRoot option

[Timeless0911]

Summary

This PR adds typescript.resolveRoot so projects can choose the root used to resolve the default TypeScript package without hard-coding typescriptPath. It applies to normal TypeScript loading, TypeScript 7+ tsgo auto-detection, and the native-preview fallback, while explicit typescriptPath continues to take precedence.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 9ab66cd5-4806-4d70-9062-8b0ddba245ea

📥 Commits

Reviewing files that changed from the base of the PR and between 6986d23 and 16636cd.

📒 Files selected for processing (1)

• src/typescript/type-script-worker-config.ts

📝 Walkthrough

Walkthrough

The PR adds resolveRoot to TypeScript worker options and config types, documents the option in the README, updates TypeScript package resolution to use an optional root path, and adds tests covering root-based resolution and TypeScript Go detection.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely summarizes the main change: adding the TypeScript resolveRoot option.
Description check	✅ Passed	The description accurately matches the changes by explaining resolveRoot, tsgo auto-detection, and precedence over typescriptPath.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch david/feat-typescript-resolve-root

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🧹 Nitpick comments (1)

test/unit/typescript/type-script-worker-config.spec.ts (1)

43-78: 📐 Maintainability & Code Quality | 🔵 Trivial | ⚡ Quick win

Add a resolveRoot test for the native-preview fallback.

The new suite covers default typescript resolution and TS 7 auto-detection, but it never exercises the tsgo: true fallback through resolveDefaultPreviewPackageJsonPath(options.resolveRoot). A small @typescript/native-preview fixture (or a parameterized package helper) plus a { tsgo: true, resolveRoot } case would lock down the third code path this PR changes.

Also applies to: 185-247

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@test/unit/typescript/type-script-worker-config.spec.ts` around lines 43 - 78,
The type-script worker config tests miss coverage for the native-preview
fallback path, so add a case in the typeScript worker config spec that uses a
resolveRoot fixture and sets tsgo: true to exercise
resolveDefaultPreviewPackageJsonPath(options.resolveRoot). Reuse the existing
createResolveRoot and createTypeScriptPackage helpers, or extend them to create
an `@typescript/native-preview` package fixture, then assert the resolved package
path/version for this third branch alongside the existing default typescript and
TS 7 detection cases.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@test/unit/typescript/type-script-worker-config.spec.ts`:
- Around line 43-78: The type-script worker config tests miss coverage for the
native-preview fallback path, so add a case in the typeScript worker config spec
that uses a resolveRoot fixture and sets tsgo: true to exercise
resolveDefaultPreviewPackageJsonPath(options.resolveRoot). Reuse the existing
createResolveRoot and createTypeScriptPackage helpers, or extend them to create
an `@typescript/native-preview` package fixture, then assert the resolved package
path/version for this third branch alongside the existing default typescript and
TS 7 detection cases.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: f1a0cedd-8570-454e-a1b9-ddf293281243

📥 Commits

Reviewing files that changed from the base of the PR and between a780128 and 6986d23.

📒 Files selected for processing (4)

• README.md
• src/typescript/type-script-worker-config.ts
• src/typescript/type-script-worker-options.ts
• test/unit/typescript/type-script-worker-config.spec.ts