feat: v4.6.0 — AI assistant, collaboration, knowledge base, and 15 more features

- AI Assistant plugin: multi-provider chat (OpenAI/Anthropic/Ollama/LM Studio),
  summarize/improve/translate commands, proofread via ai:analyze; calls
  proxied through main so API keys stay out of the renderer
- Collaboration plugin: anchor-based comments in .comments/ sidecars with
  drift detection and F8 navigation
- Local knowledge base: [[wiki-links]] with click-to-create + Backlinks panel
- Crash recovery: debounced session snapshots with restore prompt on launch
- Version history: pre-save snapshots, History panel with restore/diff/delete
- Real PDF encryption: swap pdf-lib for @cantoo/pdf-lib (probe-driven UI)
- XLSX export (native workbooks via JSZip), ODT headers/footers + page size
- Offline KaTeX (bundled CSS+fonts), local-first PlantUML rendering
- Editor: vim mode toggle, snippet Tab-expansion, zen word-goal setter,
  writing heatmap, writing-studio panels wired with rail icons
- Quick Note global scratchpad (Ctrl+Alt+Q), markdownconverter:// deep links,
  REPL first-run confirmation
- Fix: Ctrl+Shift+P collision, pandoc converter availability check, CLI
  dangling --css/--reference-doc flags, dead converter button

8 new test suites; 613 tests green; lint clean

src/plugins/plugin-context.js

@@ -58,6 +58,15 @@ class PluginContext {
       getSelection: () => editor.getSelection(),
       insertAtCursor: (text) => editor.insertAtCursor(text),
       onContentChanged: (cb) => editor.onContentChanged(cb),
+      // Current tab's file path (null for untitled tabs) — plugins that store
+      // sidecar data (comments, snapshots, …) key off this.
+      getCurrentFilePath: () => (editor.getCurrentFilePath ? editor.getCurrentFilePath() : null),
+      // Scroll the active editor to a 1-based line and place the cursor there
+      jumpToLine: (line) => {
+        if (editor.jumpToLine) editor.jumpToLine(line);
+      },
+      // 1-based line of the primary cursor
+      getCurrentLine: () => (editor.getCurrentLine ? editor.getCurrentLine() : 1),
     };
 
     this.events = {