Phase 1 MVP - Complete implementation

- Login with JWT and refresh token rotation
- Dashboard with projects cards
- ProjectView with TreeView navigation
- DocumentView with markdown editor and auto-save
- Tag management (create, assign, remove)
- Dark mode CSS variables
- Security fixes applied (logout to backend, createDocument endpoint)

node_modules/picocolors/README.md

@@ -0,0 +1,21 @@
+# picocolors
+
+The tiniest and the fastest library for terminal output formatting with ANSI colors.
+
+```javascript
+import pc from "picocolors"
+
+console.log(
+  pc.green(`How are ${pc.italic(`you`)} doing?`)
+)
+```
+
+- **No dependencies.**
+- **14 times** smaller and **2 times** faster than chalk.
+- Used by popular tools like PostCSS, SVGO, Stylelint, and Browserslist.
+- Node.js v6+ & browsers support. Support for both CJS and ESM projects.
+- TypeScript type declarations included.
+- [`NO_COLOR`](https://no-color.org/) friendly.
+
+## Docs
+Read **[full docs](https://github.com/alexeyraspopov/picocolors#readme)** on GitHub.