feat: complete analytics module self-containment

Migrate analytics module to fully self-contained structure:

- routes/api/vendor.py - API endpoints
- routes/pages/vendor.py - Page routes with full implementation
- services/stats_service.py - Business logic (moved from app/services)
- services/usage_service.py - Usage tracking (moved from app/services)
- schemas/stats.py - Pydantic schemas (moved from models/schema)
- models/__init__.py - Model exports
- templates/analytics/vendor/ - Templates (moved from app/templates)
- static/vendor/js/ - JavaScript (moved from static/vendor)
- locales/ - Translations (en, de, fr, lu)
- exceptions.py - Module exceptions

Removed legacy files:
- app/modules/analytics/routes/vendor.py (replaced by routes/pages/)
- static/admin/js/analytics.js (unused)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/modules/analytics/__init__.py

@@ -2,21 +2,34 @@
 """
 Analytics Module - Reporting and analytics.
 
-This module provides:
+This is a self-contained module providing:
 - Dashboard analytics
 - Custom reports
 - Data exports
 - Performance metrics
 
-Routes:
-- Vendor: /api/v1/vendor/analytics/*
-- (Admin uses dashboard for analytics)
-
-Menu Items:
-- Admin: (uses dashboard)
-- Vendor: analytics
+Module Structure:
+- models/ - Database models (none - uses data from other modules)
+- services/ - Business logic (StatsService, UsageService)
+- schemas/ - Pydantic DTOs
+- routes/ - API routes
+- exceptions.py - Module-specific exceptions
 """
 
-from app.modules.analytics.definition import analytics_module
+# Use lazy imports to avoid circular import issues
 
-__all__ = ["analytics_module"]
+
+def __getattr__(name: str):
+    """Lazy import module components to avoid circular imports."""
+    if name == "analytics_module":
+        from app.modules.analytics.definition import analytics_module
+
+        return analytics_module
+    elif name == "get_analytics_module_with_routers":
+        from app.modules.analytics.definition import get_analytics_module_with_routers
+
+        return get_analytics_module_with_routers
+    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
+
+
+__all__ = ["analytics_module", "get_analytics_module_with_routers"]