Remove nginx/webapp container; single Go server serves SPA + API

- Add root Dockerfile: node build → copy dist into Go embed path → distroless binary
- Update docker-compose: one service (api on :9050), DB renamed ralph→pamietnik
- Remove references to RALPH/reisejournal across all docs and configs

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/settings.gradle.kts

@@ -25,5 +25,5 @@ dependencyResolutionManagement {
     }
 }
 
-rootProject.name = "reisejournal"
+rootProject.name = "pamietnik"
 include(":app")