feat: per-position camera settings, material alias dialog, product delete, media browser links

- Per-render-position focal_length_mm/sensor_width_mm (DB → pipeline → Blender)
- FOV-based camera distance with min clamp fix for wide-angle lenses
- Unmapped materials blocking dialog on "Dispatch Renders" with batch alias creation
- Material check endpoint (GET /orders/{id}/check-materials)
- Batch alias endpoint (POST /materials/batch-aliases)
- Quick-map "No alias" badges on Materials page
- Full product hard-delete with storage cleanup (MinIO + disk files + orphaned CadFile)
- Delete button on ProductDetail page with confirmation
- Clickable product names in Media Browser (links to product page)
- Single-line render dispatch/retry (POST /orders/{id}/lines/{id}/dispatch-render)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/alembic/versions/4c15abf3cf40_add_focal_length_mm_and_sensor_width_mm_.py

@@ -0,0 +1,36 @@
+"""add focal_length_mm and sensor_width_mm to render positions
+
+Revision ID: 4c15abf3cf40
+Revises: 6ebfe2737531
+Create Date: 2026-03-14 06:31:13.141830
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = '4c15abf3cf40'
+down_revision: Union[str, None] = '6ebfe2737531'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('global_render_positions', sa.Column('focal_length_mm', sa.Float(), nullable=True))
+    op.add_column('global_render_positions', sa.Column('sensor_width_mm', sa.Float(), nullable=True))
+    op.add_column('product_render_positions', sa.Column('focal_length_mm', sa.Float(), nullable=True))
+    op.add_column('product_render_positions', sa.Column('sensor_width_mm', sa.Float(), nullable=True))
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('product_render_positions', 'sensor_width_mm')
+    op.drop_column('product_render_positions', 'focal_length_mm')
+    op.drop_column('global_render_positions', 'sensor_width_mm')
+    op.drop_column('global_render_positions', 'focal_length_mm')
+    # ### end Alembic commands ###