* feat(web): add Mermaid diagram rendering and off-thread KaTeX/Mermaid workers
Enable Mermaid diagram support in the web chat via markstream-vue's enableMermaid(). Set up Web Workers for both KaTeX rendering and Mermaid parsing using markstream-vue's pre-built workers (katexRenderer.worker, mermaidParser.worker), keeping heavy computation off the main thread during live streaming.
* fix(web): skip Mermaid SVG subtrees in file link and markdown link rewriters
processFileLinks() uses a TreeWalker that scans all text nodes in mdRef.
Mermaid diagrams render as inline SVG, and diagram labels containing
file-path-like strings (e.g. src/App.vue) would be replaced with HTML
<button> elements inside SVG <text> nodes, corrupting the rendered diagram.
processMarkdownLinks() similarly queries a[href] inside SVGs; while
isLocalLink() mostly filters these out, explicitly skipping SVG subtrees
is safer.
Add svg to the closest() exclusion in processFileLinks(), and skip
links inside svg in processMarkdownLinks().
* fix(web): satisfy worker import lint
* chore: align mermaid dependency versions
* chore: change mermaid workers changeset to patch
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Co-authored-by: qer <wbxl2000@outlook.com>
