feat(i18n): tools + landing page + doorstop generator in English

Phase 1 of full English translation:
- generate_doorstop_items.py: all 55 items (SG/SYS/SWE/SA/SWA) rewritten in English
- generate_landing_page.py: full UI labels, KPI cards, section headings in English
- traceability.py: docstring, error messages, HTML headers in English
- generate_test_report.py: report content + table headers in English
- All 55 markdown items in safety/sg/, reqs/, arch/ regenerated in English

Still to come:
- demo-epb filled Word docs (PID, plans, safety, manuals, audit artefacts)
- Code comments + test names + CI workflow step names
- README + dev-process repo templates

reqs/swe/SWE-008.md

@@ -1,7 +1,7 @@
 ---
 active: true
 derived: false
-header: 'Auto-Apply nach 2 s Verzoegerung'
+header: 'Auto-apply after 2 s delay'
 level: 1.8
 normative: true
 reviewed: null
@@ -10,6 +10,6 @@ links:
 asil: D
 ---
 
-# SWE-008: Auto-Apply nach 2 s Verzoegerung
+# SWE-008: Auto-apply after 2 s delay
 
-Ist die Motor-Aus-Bedingung 2 s stabil erfuellt und Parkbremse noch nicht aktiv, muss der Safety-Manager Apply-Anforderung an den Apply-Controller senden.
+If the engine-off condition is stable for 2 s and the parking brake is not yet active, the Safety Manager must send an apply request to the apply controller.