Set up CoreEditor as Yarn workspace (monorepo)

[Copilot]

Sets up the CoreEditor project as a Yarn workspace to support modularization as the project scales. The workspace infrastructure is now in place and ready for migrating existing modules to packages in future PRs.

Changes

• Workspace configuration: Added workspaces: ["packages/*"] to package.json and configured .yarnrc.yml
• Package structure: Created packages/ directory for modularized packages (currently empty, ready for real packages)
• Build system: Updated eslint to ignore packages/*/dist/* and .gitignore to exclude .yarn/cache/

Configuration Pattern Established

The workspace is configured to support shared configurations between packages and the root, avoiding duplication:

ESLint pattern (minimal config in packages):

import rootConfig from '../../eslint.config.mjs';
export default rootConfig;

TypeScript pattern (extends root with minimal overrides):

{
  "extends": "../../tsconfig.json",
  "compilerOptions": {
    "outDir": "./dist",
    "rootDir": "./src",
    "noEmit": true
  }
}

Benefits:

• No configuration duplication across packages
• Single source of truth for linting and TypeScript rules
• Changes to root config automatically apply to all packages
• Smaller package.json files (packages only include package-specific dependencies)

Future Usage

When packages are added to the packages/ directory, they will:

• Be automatically recognized by the workspace
• Can be referenced using workspace:* protocol in dependencies
• Share configurations and dependencies from the root
• Follow the established pattern for consistency

List workspaces:

yarn workspaces list

The root package.json remains the main entry point. The workspace infrastructure is ready for migrating existing modules to packages in subsequent PRs.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Modularizing CoreEditor</issue_title>
<issue_description>The CoreEditor project began as a small initiative and is now expanding. We should consider modularizing it to separate the business logic and enhance reusability.

To begin:

• Create a mono repo (or "workspace") for CoreEditor.
• Keep CoreEditor/package.json as the main entry point.
• Add a CoreEditor/packages folder and relocate modularized packages there.
• Add a CoreEditor/packages/markedit-hello local package for testing purposes.
• Include CoreEditor/packages/markedit-hello in CoreEditor/package.json to test the workspace.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Modularizing CoreEditor #1157

---

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[cyanzhong]

@copilot can you make modularized packages vite project, make sure eslint is enabled.

Just like the main package?

[Copilot]

Done! The markedit-hello package is now a Vite project with ESLint enabled, matching the main package structure.

Changes in commits a289871 and f17647c:

• Added Vite build system with vite.config.mts
• Added ESLint configuration with eslint.config.mjs (same rules as main package)
• Package builds to both ESM and CommonJS formats
• All lint, build, and test commands work correctly

The package now has the same dev scripts as the main package:

• yarn dev - run Vite dev server
• yarn lint - run ESLint
• yarn build - build with Vite
• yarn clean - clean dist folder

[cyanzhong]

@copilot Can it reuse configurations used in the main package instead of always needing separate config files?

[Copilot]

Yes! The package now reuses configurations from the root:

ESLint (3 lines, down from 107):

import rootConfig from '../../eslint.config.mjs';
export default rootConfig;

TypeScript (extends root with minimal overrides):

{
  "extends": "../../tsconfig.json",
  "compilerOptions": {
    "outDir": "./dist",
    "rootDir": "./src",
    "noEmit": true
  }
}

Dependencies (2 Vite-specific deps, down from 13):

• All ESLint, TypeScript, and shared tooling now come from root workspace
• Package only includes vite and vite-plugin-dts

Benefits:

• No configuration duplication
• Single source of truth
• Changes to root config automatically apply to all packages
• Much smaller package.json files

Commit: 3ddc580

[cyanzhong]

@copilot Please rebase from main.

[Copilot]

@copilot Please rebase from main.

I'm unable to perform git rebase operations as I cannot pull branches from GitHub. Could you please rebase this branch from main? After you've done that, I can continue with any additional changes if needed.

[cyanzhong]

@copilot I've tested markedit-hello and it works fine. Now please delete markedit-hello entirely, we will be migrating existing modules to packages in following PRs.

[Copilot]

@copilot I've tested markedit-hello and it works fine. Now please delete markedit-hello entirely, we will be migrating existing modules to packages in following PRs.

Done! The markedit-hello test package has been completely removed.

Removed:

• packages/markedit-hello/ directory (all files)
• test/workspace.test.ts
• markedit-hello dependency from package.json
• Updated yarn.lock

Workspace is ready:

• ✅ packages/ directory exists for future packages
• ✅ Workspace configuration (workspaces: ["packages/*"]) remains in place
• ✅ All 49 tests pass
• ✅ Build succeeds

The infrastructure is now ready for migrating existing modules to packages in future PRs.

Commit: 565befb