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.

package.json

@@ -11,6 +11,7 @@
     "@grpc/grpc-js": "^1.14.3",
     "@hattip/adapter-node": "^0.0.49",
     "@hiogawa/tiny-rpc": "^0.2.3-pre.18",
+    "@hiogawa/utils": "^1.7.0",
     "@hono/node-server": "^1.19.11",
     "@hono/zod-validator": "^0.7.6",
     "@pinia/colada": "^1.0.0",