export_to_docx: strip emoji from output filename

Merge branch 'Fu-Jie:main' into main

export_to_docx: Mermaid (Kroki), LaTeX math, real links, improved tables

- Update plugin metadata (version, requirements, description) and switch to python-docx-valutico with httpx, Pygments, latex2mathml, mathml2omml.
- Render Mermaid fences (mermaid code blocks) via Kroki PNG with caching, concurrency, timeouts/size limits, total image budget, and proper caption title extraction; strip Mermaid title before sending to Kroki.
- Convert LaTeX to real Word equations (inline \(…\) and display \[...\] / 41241...41241) with safe fallback.
- Add real clickable hyperlinks for Markdown links and bare URLs, including inside tables and inside inline-code spans (preserving code styling).
- Improve table formatting (compact sizing, margins/spacing, header repeat, zebra striping, alignment parsing, width heuristics) and refactor inline formatting parsing for correct nesting.
- Switch normal text to Word-default fonts (Normal style Calibri) and keep Consolas for code.

docs(copilot-instructions): add release workflow guidelines

- Add release workflow section with automatic release process
- Document version numbering rules (semver)
- Add three release methods: direct push, PR, manual trigger
- Include commit message convention (Conventional Commits)
- Add release checklist