Add admin CLI command and auth guard, use oRPC client

CLI changes:
- Use official oRPC client instead of manual HTTP requests
- Add admin complete-login command for dev workflow
- Remove type assertions, use proper ContractRouterClient typing
- Add @orpc/client and @orpc/contract dependencies

API changes:
- Use oRPC cookie helpers from @orpc/server/helpers
- Improve admin complete-login error messages (expired, already completed)

Dashboard changes:
- Add AuthGuard component to redirect unauthenticated users to /auth/login
- Update confirm page with correct CLI command and copy button
- Remove duplicate auth redirect from dashboard layout

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

bun.lock

@@ -48,11 +48,14 @@
       "name": "@reviq/cli",
       "version": "0.0.0",
       "bin": {
-        "reviq": "./dist/index.js",
-        "__reviq_bash_complete": "./dist/bash-complete.js",
+        "reviq": "./dist/reviq",
+        "__reviq_bash_complete": "./dist/bash-complete",
       },
       "dependencies": {
         "@noble/hashes": "^2.0.1",
+        "@orpc/client": "^1.13.2",
+        "@orpc/contract": "^1.13.2",
+        "@reviq/api-contract": "workspace:*",
         "@reviq/db": "workspace:*",
         "@scure/base": "^2.0.0",
         "@stricli/auto-complete": "^1.0.0",