add composer-unused, comprehensive docs, and project restructure

- Add icanhazstring/composer-unused as dev dependency for dependency hygiene checks
- Add German documentation (docs/) covering architecture, conventions, workflows, and developer checklists
- Add API layer (ApiAuth, ApiBootstrap, ApiResponse), audit, scheduler, custom fields, and SSO services
- Add Microsoft OIDC SSO, API token management, and user lifecycle features
- Add swagger-ui vendor integration and OpenAPI spec
- Add production Docker setup and bin/ scripts
- Update composer dependencies, config, templates, and frontend assets throughout

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

web/css/components/app-badges.css

@@ -1,3 +1,4 @@
+@layer components {
 .badge[role="button"],
 .badge {
   display: inline-flex;
@@ -68,6 +69,18 @@
   border-color: var(--badge-info-border);
 }
 
+.badge[data-variant="primary"] {
+  background: var(--badge-info-bg);
+  color: var(--badge-info-color);
+  border-color: var(--badge-info-border);
+}
+
+.badge[data-variant="secondary"] {
+  background: var(--badge-neutral-bg);
+  color: var(--badge-neutral-color);
+  border-color: var(--badge-neutral-border);
+}
+
 .badge[data-variant="warn"] {
   background: var(--badge-warn-bg);
   color: var(--badge-warn-color);
@@ -105,3 +118,4 @@
   display: flex;
   gap: 0.35rem;
 }
+}