feat: add admin components for input, metrics, tables, and user forms

- Introduced AdminInput component for standardized input fields.
- Created AdminMetricCard for displaying metrics with customizable tones.
- Added AdminPlaceholderTable for loading states in tables.
- Developed AdminSectionCard for consistent section layouts.
- Implemented AdminSectionShell for organizing admin sections.
- Added AdminSelect for dropdown selections with v-model support.
- Created AdminTable for displaying tabular data with loading and empty states.
- Introduced AdminTextarea for multi-line text input.
- Developed AdminUserFormFields for user creation and editing forms.
- Added useAdminPageHeader composable for managing admin page header state.

tsconfig.json

@@ -1,5 +1,7 @@
 {
   "compilerOptions": {
+    "allowImportingTsExtensions": true,
+    "noEmit": true,
     "target": "ESNext",
     "module": "ESNext",
     "moduleResolution": "Bundler",