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.

bun.lock

@@ -9,6 +9,7 @@
         "@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",
@@ -176,6 +177,8 @@
 
     "@hiogawa/tiny-rpc": ["@hiogawa/tiny-rpc@0.2.3-pre.18", "", {}, "sha512-BiNHrutG9G9yV622QvkxZxF+PhkaH2Aspp4/X1KYTfnaQTcg4fFUTBWf5Kf533swon2SuVJwi6U6H1LQbhVOQQ=="],
 
+    "@hiogawa/utils": ["@hiogawa/utils@1.7.0", "", {}, "sha512-ghiEFWBR1NENoHn+lSuW7liicTIzVPN+8Srm5UedCTw43gus0mlse6Wp2lz6GmbOXJ/CalMPp/0Tz2X8tajkAg=="],
+
     "@hono/node-server": ["@hono/node-server@1.19.11", "", { "peerDependencies": { "hono": "^4" } }, "sha512-dr8/3zEaB+p0D2n/IUrlPF1HZm586qgJNXK1a9fhg/PzdtkK7Ksd5l312tJX2yBuALqDYBlG20QEbayqPyxn+g=="],
 
     "@hono/zod-validator": ["@hono/zod-validator@0.7.6", "", { "peerDependencies": { "hono": ">=3.9.0", "zod": "^3.25.0 || ^4.0.0" } }, "sha512-Io1B6d011Gj1KknV4rXYz4le5+5EubcWEU/speUjuw9XMMIaP3n78yXLhjd2A3PXaXaUwEAluOiAyLqhBEJgsw=="],