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>

backend/app/services/step_processor.py

@@ -345,7 +345,8 @@ def extract_mesh_edge_data(step_path: str) -> dict:
                         [round(pt_start.X(), 3), round(pt_start.Y(), 3), round(pt_start.Z(), 3)],
                         [round(pt_end.X(), 3), round(pt_end.Y(), 3), round(pt_end.Z(), 3)],
                     ])
-            except Exception:
+            except Exception as _exc:
+                logger.debug("Edge dihedral angle calc failed (skipping edge): %s", _exc)
                 continue
 
         # Bounding box
@@ -373,7 +374,8 @@ def extract_mesh_edge_data(step_path: str) -> dict:
                 "y": round((ymin + ymax) / 2, 2),
                 "z": round((zmin + zmax) / 2, 2),
             }
-        except Exception:
+        except Exception as _exc:
+            logger.debug("Bounding box calc failed: %s", _exc)
             dimensions_mm = None
             bbox_center_mm = None
 
@@ -580,7 +582,8 @@ def extract_step_metadata(step_path: str) -> StepMetadata:
                             [round(pt_start.X(), 3), round(pt_start.Y(), 3), round(pt_start.Z(), 3)],
                             [round(pt_end.X(), 3), round(pt_end.Y(), 3), round(pt_end.Z(), 3)],
                         ])
-                except Exception:
+                except Exception as _exc:
+                    logger.debug("Edge dihedral angle calc failed (skipping edge): %s", _exc)
                     continue
 
         # ── Step 4: Bounding box ──────────────────────────────────────────
@@ -601,8 +604,8 @@ def extract_step_metadata(step_path: str) -> StepMetadata:
                 "y": round((ymin + ymax) / 2, 2),
                 "z": round((zmin + zmax) / 2, 2),
             }
-        except Exception:
-            pass
+        except Exception as _exc:
+            logger.debug("Bounding box calc failed: %s", _exc)
 
         # ── Step 5: Build edge_data dict ──────────────────────────────────
         edge_data: dict = {}
@@ -866,8 +869,8 @@ def extract_rich_metadata(step_path: str) -> dict:
                     if vol > largest_volume:
                         largest_volume = vol
                         largest_name = name
-                except Exception:
-                    pass
+                except Exception as _exc:
+                    logger.debug("Volume properties failed for part '%s': %s", name, _exc)
 
                 try:
                     props = GProp_GProps()
@@ -877,8 +880,8 @@ def extract_rich_metadata(step_path: str) -> dict:
                         brepgprop.SurfaceProperties(shape, props)
                     area = abs(props.Mass())  # mm²
                     total_area += area * count
-                except Exception:
-                    pass
+                except Exception as _exc:
+                    logger.debug("Surface area properties failed for part '%s': %s", name, _exc)
 
         result["total_volume_cm3"] = round(total_volume / 1000.0, 2)     # mm³ → cm³
         result["total_surface_area_cm2"] = round(total_area / 100.0, 2)  # mm² → cm²
@@ -900,8 +903,8 @@ def extract_rich_metadata(step_path: str) -> dict:
                 min_dim = min(d for d in dims if d > 1e-6)  # skip degenerate
                 if min_dim < smallest_dim:
                     smallest_dim = min_dim
-            except Exception:
-                pass
+            except Exception as _exc:
+                logger.debug("Smallest dimension calc failed for shape: %s", _exc)
         result["smallest_dimension_mm"] = round(smallest_dim, 2) if smallest_dim < float("inf") else 0.0
 
         # ── Triangle and vertex counts from tessellation ──────────────────
@@ -928,8 +931,8 @@ def extract_rich_metadata(step_path: str) -> dict:
                         if tri is not None:
                             total_triangles += tri.NbTriangles()
                             total_vertices += tri.NbNodes()
-                    except Exception:
-                        pass
+                    except Exception as _exc:
+                        logger.debug("Triangle count failed for face: %s", _exc)
                     explorer.Next()
 
         result["total_triangle_count"] = total_triangles
@@ -1015,8 +1018,8 @@ def _extract_step_objects_fallback(step_path: Path) -> list[str]:
                             name = part.split("'")[1]
                             if name and name not in names:
                                 names.append(name)
-    except Exception:
-        pass
+    except Exception as _exc:
+        logger.warning("STEP raw text parse for product names failed: %s", _exc)
     return names