chore: trim Shiki client bundles, patch @pierre/diffs, diffkit theme names

[stylessh]

Summary

This PR reduces client bundle weight from Shiki and @pierre/diffs by avoiding the default shiki entry (which references every language/theme chunk), and renames custom markdown highlighter themes from vercel-* to diffkit-*.

Changes

• Markdown / @diffkit/ui: createHighlighterCore from shiki/core with explicit @shikijs/langs imports, JS regex engine, and custom diffkit-light / diffkit-dark themes. Unknown fence languages fall back to plain text.
• @pierre/diffs: pnpm patch replaces bundledLanguages / bundledThemes imports, uses createHighlighterCore for the shared highlighter, and resolves themes only via registered custom themes. Language loading uses an allowlisted set of @shikijs/langs with a small ini fallback for rare file types.
• Workspace: pnpm.overrides pin @pierre/diffs to Shiki 4 and matching @shikijs/transformers; patchedDependencies applies the patch.

Notes

• Client build should show far fewer duplicate/heavy grammar chunks (e.g. duplicate WASM, emacs-lisp).
• Full vite build may still fail on the SSR step (cloudflare:workers) if that was already an issue locally; unrelated to this PR.

Summary by CodeRabbit

• New Features
  • Improved code block rendering with deterministic language recognition, a curated bundled language set, and new light/dark token palettes for more consistent highlighting.
• Chores
  • Updated syntax-highlighting packages and added package-manager overrides and a local patch to stabilize behavior.
• Bug Fixes
  • Removed runtime language-loading fallbacks to reduce flicker and improve reliability.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 6ea4979 and 4102d0a.

⛔ Files ignored due to path filters (1)

• pnpm-lock.yaml is excluded by !**/pnpm-lock.yaml

📒 Files selected for processing (2)

• packages/ui/src/components/markdown.tsx
• patches/@pierre__diffs@1.1.12.patch

🚧 Files skipped from review as they are similar to previous changes (2)

• packages/ui/src/components/markdown.tsx
• patches/@pierre__diffs@1.1.12.patch

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📝 Walkthrough

Walkthrough

Added pnpm overrides and a local patch for @pierre/diffs; introduced a Shiki bundle module with deterministic bundled-language loaders, swapped theme identifiers from vercel-* to diffkit-*, and updated markdown highlighting to use a new createMarkdownHighlighter() with normalized fence-language handling.

Changes

Cohort / File(s)	Summary
Package manager & patch package.json, patches/@pierre__diffs@1.1.12.patch	Added pnpm overrides and patchedDependencies; patch rewrites bundled highlighting to use @shikijs/* packages, dynamic per-language loaders, createHighlighterCore usage, and theme normalization changes.
Shiki theme & bundle infrastructure packages/ui/src/lib/shiki-themes.ts, packages/ui/src/lib/shiki-bundle.ts, packages/ui/src/lib/diffs-themes.ts	Renamed exported themes from vercelLight/vercelDark to diffkitLight/diffkitDark (names "diffkit-light"/"diffkit-dark"). Added shiki-bundle.ts exporting SHIKI_BUNDLED_LANGS, ShikiBundledLang type, shikiBundledLangSet, and createMarkdownHighlighter() factory. Updated comments and token palette references.
UI package & markdown integration packages/ui/package.json, packages/ui/src/components/markdown.tsx	Added @shikijs/langs@4.0.2 dependency. markdown.tsx now uses createMarkdownHighlighter(), replaces runtime language loading with FENCE_LANG_ALIASES + shikiBundledLangSet checks, and switches theme IDs to diffkit-light/diffkit-dark.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the main objectives: trimming Shiki bundles, patching @pierre/diffs, and renaming theme identifiers to diffkit.
Description check	✅ Passed	The description includes a comprehensive Summary, detailed Changes section, and Notes explaining implications. However, it lacks a Test Plan section with checkboxes and Screenshots section from the template.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch chore/shiki-bundle-trim-diffkit-themes

---

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[coderabbitai]

Actionable comments posted: 3

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.
Inline comments:
In `@packages/ui/src/components/markdown.tsx`:
- Around line 22-34: FENCE_LANG_ALIASES is missing common Shiki fence aliases so
languages like yml, gql, and md fall back to plain text; update the
FENCE_LANG_ALIASES map in components/markdown.tsx (type ShikiBundledLang) to
include at least these mappings: "yml" -> "yaml", "yaml" -> "yaml" (if not
present), "gql" -> "graphql", "graphql" -> "graphql" (if not present), and "md"
-> "markdown" (and "markdown" -> "markdown" if missing) so Shiki receives
canonical language names and highlighting is preserved. Ensure you add only
aliases that map to valid ShikiBundledLang entries used elsewhere in the file.
In `@patches/`@pierre__diffs@1.1.12.patch:
- Around line 14-44: The patch adds dynamic imports like javascript: () =>
import("@shikijs/langs/javascript") and uses `@shikijs/core` but package.json for
`@pierre/diffs`@1.1.12 doesn’t declare `@shikijs/core` or any `@shikijs/langs/`*
packages; update the package manifest to add `@shikijs/core` plus each required
language package (e.g. `@shikijs/langs/javascript`, `@shikijs/langs/typescript`,
`@shikijs/langs/jsx`, `@shikijs/langs/tsx`, `@shikijs/langs/json`,
`@shikijs/langs/html`, `@shikijs/langs/css`, `@shikijs/langs/bash`,
`@shikijs/langs/shellscript`, `@shikijs/langs/python`, `@shikijs/langs/go`,
`@shikijs/langs/rust`, `@shikijs/langs/yaml`, `@shikijs/langs/markdown`,
`@shikijs/langs/diff`, `@shikijs/langs/sql`, `@shikijs/langs/graphql`,
`@shikijs/langs/ruby`, `@shikijs/langs/java`, `@shikijs/langs/c`, `@shikijs/langs/cpp`,
`@shikijs/langs/swift`, `@shikijs/langs/kotlin`, `@shikijs/langs/dockerfile`,
`@shikijs/langs/toml`, `@shikijs/langs/vue`, `@shikijs/langs/svelte`,
`@shikijs/langs/php`, `@shikijs/langs/csharp`, `@shikijs/langs/ini`) with appropriate
versions (or a single compatible range), or alternatively consolidate imports to
only the langs that are truly needed and add those to dependencies; ensure
lockfile is updated and CI passes.
- Around line 12-45: The trimmedBundledLanguages map lacks common aliases so
resolveLanguage falls back to ini for inputs like "js", "ts", "py", "rb", "gql",
"md", "yml", "c++", etc.; update resolveLanguage or trimmedBundledLanguages to
include those aliases (or normalize inputs) so aliases map to the intended keys
(e.g., map "js" -> "javascript", "ts" -> "typescript", "py" -> "python", "rb" ->
"ruby", "gql" -> "graphql", "md" -> "markdown", "yml" -> "yaml", "c++" ->
"cpp"), and ensure resolveLanguage first checks the alias map before falling
back to ini (reference trimmedBundledLanguages and resolveLanguage in the diff).

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 7dc071a7-c937-451f-bdf1-d2c7f1449fe0

📥 Commits

Reviewing files that changed from the base of the PR and between 95ea21b and 6ea4979.

⛔ Files ignored due to path filters (1)

• pnpm-lock.yaml is excluded by !**/pnpm-lock.yaml

📒 Files selected for processing (7)

• package.json
• packages/ui/package.json
• packages/ui/src/components/markdown.tsx
• packages/ui/src/lib/diffs-themes.ts
• packages/ui/src/lib/shiki-bundle.ts
• packages/ui/src/lib/shiki-themes.ts
• patches/@pierre__diffs@1.1.12.patch