chore: simplify .gitignore for personal vault, add plugins

Cleaned up .gitignore (removed upstream author-specific entries, added
.claude/ and excalidraw main.js). Track installed Obsidian plugins:
dataview, templater, obsidian-git, local-rest-api.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.obsidian/plugins/dataview/manifest.json

@@ -0,0 +1,11 @@
+{
+  "id": "dataview",
+  "name": "Dataview",
+  "version": "0.5.68",
+  "minAppVersion": "0.13.11",
+  "description": "Complex data views for the data-obsessed.",
+  "author": "Michael Brenan <blacksmithgu@gmail.com>",
+  "authorUrl": "https://github.com/blacksmithgu",
+  "helpUrl": "https://blacksmithgu.github.io/obsidian-dataview/",
+  "isDesktopOnly": false
+}