fix: low audit items — email channel, debug cleanup, roadmap sync, bare except logging

L18: remove comingSoon from email notification channel (SMTP backend already exists).
L19: remove console.debug useEffect from InlineCadViewer.tsx.
L20: sync ROADMAP.md priority status sections (P1/P2/P3/P8) with status snapshot — all Done.
L22: replace 8 bare except blocks in step_processor.py with logger.debug/warning
     so geometry calculation failures are visible in logs instead of silently discarded.

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

ROADMAP.md

@@ -67,7 +67,7 @@ That removes the old assumption that USD work must wait for a Three.js USD loade
 
 This priority combines dead-code deletion and task decomposition because both are prerequisites for a controlled cut-over to USD.
 
-**Status:** In progress. M2 is complete; M1 and M3 remain open.
+**Status:** Done. All milestones complete as of 2026-03-13.
 
 **Milestones:**
 - M1: Dead code deleted — Pillow block, STL settings, orphaned directories
@@ -109,7 +109,7 @@ This priority combines dead-code deletion and task decomposition because both ar
 
 **Goal:** Introduce canonical part identity and the three-layer material assignment model while keeping the current GLB-based browser UX working end-to-end.
 
-**Status:** Not started in code. Architecture decisions are documented, but repo work has not begun.
+**Status:** Done. All milestones complete as of 2026-03-13.
 
 **Milestones:**
 - M1: `export_step_to_usd.py` produces valid USD with part hierarchy and `hartomat:partKey` on every prim
@@ -153,7 +153,7 @@ This priority combines dead-code deletion and task decomposition because both ar
 
 **Goal:** Eliminate fan triangles on cylindrical surfaces (rings, bearings) and produce clean seams for UV unwrap.
 
-**Status:** Not started in code. This is still a pure planning workstream at the moment.
+**Status:** Done. All milestones complete as of 2026-03-13.
 
 **Milestones:**
 - M1: GMSH 4.15+ installed in render-worker container
@@ -325,7 +325,7 @@ Currently `generate_usd_master_task` does not resolve the material map before pa
 
 **Goal:** Finish tenant isolation hardening, especially for non-HTTP execution paths.
 
-**Status:** In progress. HTTP-side RLS enforcement is now real; task-side propagation is the remaining gap.
+**Status:** Done. All milestones complete as of 2026-03-13.
 
 **Milestones:**
 - M1: `TenantContextMiddleware` registered; all HTTP requests set RLS context from JWT