feat: Enhance Obsidian Halo Plugin with comprehensive design system and component styles

- Updated styles.css to implement a three-layer design token architecture: Primitive, Semantic, and Component.
- Introduced new CSS variables for colors, spacing, typography, and shadows.
- Developed styles for buttons, cards, inputs, textareas, selects, badges, tables, modals, forms, color pickers, empty states, and loading spinners.
- Improved sync status view with responsive design and enhanced UI elements.
- Added skeleton loading animations for better user experience.

chore: Add configuration files for development environment

- Created .claude/settings.json to enable commit commands plugin.
- Added .vscode/c_cpp_properties.json for C/C++ IntelliSense configuration.
- Introduced .vscode/launch.json for debugging C/C++ applications with GDB.

.vscode/c_cpp_properties.json

@@ -0,0 +1,18 @@
+{
+  "configurations": [
+    {
+      "name": "windows-gcc-x64",
+      "includePath": [
+        "${workspaceFolder}/**"
+      ],
+      "compilerPath": "D:/settings/Language/C/mingw64/bin/gcc.exe",
+      "cStandard": "c17",
+      "cppStandard": "c++17",
+      "intelliSenseMode": "windows-gcc-x64",
+      "compilerArgs": [
+        ""
+      ]
+    }
+  ],
+  "version": 4
+}