Add print cover fields and office profile

- Project settings gain siteAddress, workStage, projectLead and
  projectEditor (project.update-settings schema version 3, migration 0009);
  versions 2 and 1 stay executable and keep the current cover values.
  Snapshot schema 6 carries the fields; older versions upgrade with null.
- Global office profile (office name/address) next to the document logo:
  table document_branding_settings, PUT /api/document-branding/office,
  editable from the print view toolbar.
- Cover page reads all fields; empty values show the "[ergänzen]" marker.
  The Planstände editor column shows the project editor.
- Shared logo constants moved to a dependency-free module so the Next.js
  bundler can import them.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/db-verify-circuit-schema.js

@@ -13,6 +13,7 @@ const requiredTables = [
   "distribution_board_components",
   "distribution_board_component_protection_devices",
   "document_branding_assets",
+  "document_branding_settings",
 ];
 
 const tablePlaceholders = requiredTables.map(() => "?").join(", ");
@@ -88,6 +89,10 @@ const requiredProjectColumns = [
   "description",
   "is_public_building",
   "enabled_distribution_board_supply_types",
+  "site_address",
+  "work_stage",
+  "project_lead",
+  "project_editor",
 ];
 const projectColumns = new Set(
   db.prepare("PRAGMA table_info(projects)").all().map((column) => column.name)