Enhance editor with KaTeX support for math rendering.

[oupadhyay]

Hey again, this PR resolves #57.

It does the following:

• Use @aarkue/tiptap-math-extension package for TipTap Editor Math Rendering.
• Added new CSS variables for code styling with light & dark mode values.
• Improve preview from div to read-only editor.

[oupadhyay]

[Copilot]

Pull Request Overview

This PR integrates KaTeX-based math rendering into the TipTap editor and preview, refactors code block styling to use CSS variables, and updates build scripts and dependencies.

• Add @aarkue/tiptap-math-extension and KaTeX styling for in-editor and read-only previews
• Replace raw HTML preview with a read-only TipTap editor instance
• Introduce --code-primary CSS variable and adjust build scripts/dependencies

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

File	Description
src/renderer/pages/Pile/Editor/index.jsx	Integrated MathExtension, created a read-only editor for preview, replaced dangerouslySetInnerHTML with EditorContent
src/renderer/pages/Pile/Editor/ProseMirror.scss	Updated code block styles to use --code-primary variable
src/renderer/App.scss	Defined --code-primary for light and dark themes
package.json	Switched build script to pnpm, added KaTeX and math-extension dependencies, updated module mapping and versions

Comments suppressed due to low confidence (4)

src/renderer/pages/Pile/Editor/index.jsx:173

• There are no tests verifying that the read-only editor correctly renders KaTeX math content. Adding unit or integration tests for math blocks in preview mode would help guard against regressions.

const readOnlyEditor = useEditor({

src/renderer/pages/Pile/Editor/index.jsx:177

• The Link extension is referenced in the read-only editor config but not imported. Please add import Link from '@tiptap/extension-link'; at the top to prevent a ReferenceError.

Link,

src/renderer/pages/Pile/Editor/index.jsx:127

• [nitpick] The same extensions array (StarterKit, Typography, MathExtension, etc.) is duplicated for editable and read-only editors. Consider extracting the shared extensions into a constant to reduce duplication and simplify future updates.

MathExtension.configure({

package.json:30

• [nitpick] The build script now uses pnpm instead of npm. Please verify that this matches the project's documented package manager and update any onboarding/docs to prevent contributor confusion.

"build": "concurrently \"pnpm run build:main\" \"pnpm run build:renderer\"",