Add foundational API client, UI components, and state management setup

- Created `generate-api-client.sh` for OpenAPI-based TypeScript client generation.
- Added `src/lib/api` with Axios-based API client, error handling utilities, and placeholder for generated types.
- Implemented Zustand-based `authStore` for user authentication and token management.
- Integrated reusable UI components (e.g., `Dialog`, `Select`, `Textarea`, `Sheet`, `Separator`, `Checkbox`) using Radix UI and utility functions.
- Established groundwork for client-server integration, state management, and modular UI development.

frontend/package-lock.json

@@ -13,6 +13,7 @@
         "@radix-ui/react-checkbox": "^1.3.3",
         "@radix-ui/react-dialog": "^1.1.15",
         "@radix-ui/react-dropdown-menu": "^2.1.16",
+        "@radix-ui/react-icons": "^1.3.2",
         "@radix-ui/react-label": "^2.1.7",
         "@radix-ui/react-popover": "^1.1.15",
         "@radix-ui/react-select": "^2.2.6",
@@ -21,6 +22,7 @@
         "@radix-ui/react-tabs": "^1.1.13",
         "@tanstack/react-query": "^5.90.5",
         "axios": "^1.13.1",
+        "class-variance-authority": "^0.7.1",
         "clsx": "^2.1.1",
         "date-fns": "^4.1.0",
         "lucide-react": "^0.552.0",
@@ -2682,6 +2684,15 @@
         }
       }
     },
+    "node_modules/@radix-ui/react-icons": {
+      "version": "1.3.2",
+      "resolved": "https://registry.npmjs.org/@radix-ui/react-icons/-/react-icons-1.3.2.tgz",
+      "integrity": "sha512-fyQIhGDhzfc9pK2kH6Pl9c4BDJGfMkPqkyIgYDthyNYoNg3wVhoJMMh19WS4Up/1KMPFVpNsT2q3WmXn2N1m6g==",
+      "license": "MIT",
+      "peerDependencies": {
+        "react": "^16.x || ^17.x || ^18.x || ^19.0.0 || ^19.0.0-rc"
+      }
+    },
     "node_modules/@radix-ui/react-id": {
       "version": "1.1.1",
       "resolved": "https://registry.npmjs.org/@radix-ui/react-id/-/react-id-1.1.1.tgz",
@@ -5336,6 +5347,18 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/class-variance-authority": {
+      "version": "0.7.1",
+      "resolved": "https://registry.npmjs.org/class-variance-authority/-/class-variance-authority-0.7.1.tgz",
+      "integrity": "sha512-Ka+9Trutv7G8M6WT6SeiRWz792K5qEqIGEGzXKhAE6xOWAY6pPH8U+9IY3oCMv6kqTmLsv7Xh/2w2RigkePMsg==",
+      "license": "Apache-2.0",
+      "dependencies": {
+        "clsx": "^2.1.1"
+      },
+      "funding": {
+        "url": "https://polar.sh/cva"
+      }
+    },
     "node_modules/client-only": {
       "version": "0.0.1",
       "resolved": "https://registry.npmjs.org/client-only/-/client-only-0.0.1.tgz",