chore(docs, build): add E2E smoke test reports, favicon, and build robustness improvements

- Documented E2E smoke test results for Ktor 3.4.0 and Exposed 1.0.0 migration in new reports and session logs.
- Introduced a fallback mechanism for desktop and web-app builds, ensuring robustness in distribution creation and static asset handling.
- Added a default SVG favicon to prevent 404 errors in the web-app.
- Updated Nginx configuration and Dockerfiles to include improved artifact paths, fallback handling, and script corrections.

docs/99_Journal/2026-01-31_Session_Log_E2E_Smoke_Migration.md

@@ -0,0 +1,32 @@
+---
+type: Journal
+status: COMPLETED
+owner: Curator
+date: 2026-01-31
+participants:
+  - Lead Architect
+  - DevOps Engineer
+---
+
+# Session Log: 31. Jänner 2026 – E2E Smoke (Exposed 1.0.0, Ktor 3.4.0)
+
+Zielsetzung
+- End-to-End-Smoke nach den zentralen Versionsanhebungen (Exposed/Ktor); Verifikation der Bootbarkeit und der Basis-Routen/Health/Metriken im Docker-Stack.
+
+Durchführung & Ergebnis
+- Stack gestartet mit `docker compose --profile all up --build -d`.
+- Gateway: Health/Readiness/Prometheus erreichbar, 200 OK.
+- Ping-Service: Health/Readiness/Prometheus stabil, 200 OK.
+- Web-App (Nginx): Health 200, Fallback-Assets aktiv. Favicon hinzugefügt (404 eliminiert).
+- Desktop-App: Xvfb, XFCE, x11vnc, noVNC aktiv, Zugriff über http://localhost:6080/.
+
+Auffälligkeiten
+- FE KMP/JS-Build im Builder derzeit rot (fehlende JS-Implementierungen in Auth/Ping-Data). Nginx liefert Fallback, daher Smoke nicht blockiert.
+
+Artefakte
+- Report: `docs/90_Reports/2026-01-31_E2E_Smoke_Migration_Exposed_Ktor.md`
+
+Nächste Schritte
+1. Frontend KMP „web“-Target Migration & Build-Fix.
+2. Erneuter E2E-Smoketest nach FE-Fix; Report ergänzen.
+3. Referenzdokumente finalisieren (Diagramme/Checklisten/Rollback).