feat(i18n): remaining German comments + CI strings in English

Final residual translations found in code/comments/CI:
- .doorstop.yml: config comments, traceability mapping comments
- Doxyfile: header comment
- tools/render_plantuml.py: docstring
- tools/generate_test_report.py: docstring
- tests/unit_test_framework.h: doxygen brief + body
- tests/unit/test_safety_manager.c: section comment
- src/stubs/*.h: doxygen briefs for diag/display/inclinometer/logger/service/wheel-speed
- .gitea/workflows/release.yml: release notes 'Statische Analyse' + deploy error message

src/stubs/wheel_speed_plausi.h

@@ -1,6 +1,6 @@
 /**
  * @file wheel_speed_plausi.h
- * @brief Wheel-Speed-Plausibilisierung + Stillstands-Erkennung.
+ * @brief Wheel-speed plausibility + standstill detection.
  *
  * @arch SWA-004
  * @reqs SWE-022 SWE-023