feat(plugins): expose static CodeMirror highlighter

[bajrangCoder]

• update plugin types
• update the docs

[greptile-apps]

Greptile Summary

The PR exposes the static CodeMirror highlighter through Acode’s plugin API and lets custom editor tabs adopt its theme-aware styles.

• Adds public highlighting, cache, stylesheet, and CSS-class APIs.
• Adds opt-in highlighting styles for custom-tab shadow roots.
• Keeps fallback and constructed styles synchronized with editor-theme changes.
• Adds unit and integration coverage, including detached shadow hosts.

Confidence Score: 5/5

The PR appears safe to merge.

The fallback style remains registered while its detached shadow host still owns it, and theme changes update its CSS; no blocking failure remains.

Important Files Changed

Filename	Overview
src/utils/codeHighlight.js	Adds reusable theme-aware stylesheet APIs and correctly retains detached fallback styles so subsequent theme updates continue synchronizing them.
src/lib/acode.js	Exposes a frozen static-highlighter module through both codeHighlight and codemirror.highlight plugin entry points.
src/lib/editorFile.js	Allows custom editor tabs to opt into static highlighting styles within their shadow roots.
tests/unit/codeHighlight.test.js	Covers highlighting, escaping, stylesheet adoption, duplicate prevention, theme synchronization, and the previously reported detached-host fallback behavior.

_{Reviews (2): Last reviewed commit: "fix" | Re-trigger Greptile}

[bajrangCoder]

@greptile