Extract groombook/api from monorepo with CI workflow

- Add source code from apps/api
- Add packages/db and packages/types workspace dependencies
- Add GitHub Actions CI workflow (lint, typecheck, test, docker)
- Generate pnpm-lock.yaml
- Add .gitignore

Co-Authored-By: Paperclip <noreply@paperclip.ing>

eslint.config.js

@@ -0,0 +1,11 @@
+import tseslint from "typescript-eslint";
+
+export default tseslint.config(
+  ...tseslint.configs.recommended,
+  {
+    rules: {
+      "@typescript-eslint/no-explicit-any": "warn",
+      "@typescript-eslint/no-unused-vars": ["error", { argsIgnorePattern: "^_" }],
+    },
+  }
+);