feat: editor improvements and architectural grid prototype

Multiple feature additions and improvements across the application:

- NextGen Editor: drag handles, smart paste, block actions
- Structured views: Kanban and table layouts for notes
- Architectural Grid: new brainstorming/agent interface prototype
- Flashcards: SM-2 revision algorithm with AI generation
- MCP server: robustness improvements
- Graph/PDF chat: fix click propagation and copy behavior
- Various UI/UX enhancements and bug fixes

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

architectural-grid1/tsconfig.json

@@ -0,0 +1,26 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "experimentalDecorators": true,
+    "useDefineForClassFields": false,
+    "module": "ESNext",
+    "lib": [
+      "ES2022",
+      "DOM",
+      "DOM.Iterable"
+    ],
+    "skipLibCheck": true,
+    "moduleResolution": "bundler",
+    "isolatedModules": true,
+    "moduleDetection": "force",
+    "allowJs": true,
+    "jsx": "react-jsx",
+    "paths": {
+      "@/*": [
+        "./*"
+      ]
+    },
+    "allowImportingTsExtensions": true,
+    "noEmit": true
+  }
+}