feat(w1): maven skeleton + CI scaffold

- Parent POM: de.platesoft:plate-auth-parent with ${revision} CI-friendly versioning
- plate-auth-starter module: Spring Boot 4.1.0 starter deps (web, jpa, security, validation, jwt, flyway, envers)
- @platesoft/auth npm package skeleton: tsup bundler, conditional exports, TypeScript strict
- Gitea Actions: ci.yml (on push/PR) + release.yml (on v* tag)
- distributionManagement pointing to Gitea Package Registry (Maven + npm)
- Apache-2.0 LICENSE, README with quickstart, CHANGELOG, .editorconfig, .gitignore
- pnpm workspace with packages/auth
- Maven BUILD SUCCESS verified locally

packages/auth/src/middleware/index.ts

@@ -0,0 +1,8 @@
+// Placeholder — W3 implementation
+export interface MiddlewareOptions {
+  publicPaths?: string[];
+}
+
+export function createAuthMiddleware(_opts?: MiddlewareOptions): any {
+  throw new Error('Not yet implemented — Sprint 0 W3');
+}