Add oRPC API contract with Zod schemas

- Create @reviq/api-contract package
- Define Zod schemas for all input/output types:
  - Auth schemas (signup, login, password reset, WebAuthn)
  - User/profile schemas
  - Organization schemas (CRUD, members, invites)
  - Admin procedure schemas
- Define oRPC contract with full procedure signatures:
  - auth.* (signup, login, password reset, WebAuthn)
  - me.* (profile, sessions, devices, passkeys)
  - orgs.* (CRUD, members, invites, sites)
  - admin.* (orgs, users, auth management)

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

packages/api-contract/tsconfig.json

@@ -0,0 +1,12 @@
+{
+  "extends": "@macalinao/tsconfig/tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "declaration": true,
+    "declarationMap": true,
+    "isolatedDeclarations": false
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist"]
+}