Restructure: Move 43 files into 8 domain packages (backend-lehrer)

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

backend-lehrer/units/api.py

@@ -0,0 +1,57 @@
+# ==============================================
+# Breakpilot Drive - Unit API (barrel re-export)
+# ==============================================
+# This module was split into:
+#   - unit_models.py      (Pydantic models)
+#   - unit_helpers.py      (Auth, DB, token, validation helpers)
+#   - unit_routes.py       (Definition, session, analytics routes)
+#   - unit_content_routes.py (H5P, worksheet, PDF routes)
+#
+# The `router` object is assembled here by including all sub-routers.
+# Importers that did `from unit_api import router` continue to work.
+
+from fastapi import APIRouter
+
+from .routes import router as _routes_router
+from .definition_routes import router as _definition_router
+from .content_routes import router as _content_router
+
+# Re-export models for any direct importers
+from .models import (  # noqa: F401
+    UnitDefinitionResponse,
+    CreateSessionRequest,
+    SessionResponse,
+    TelemetryEvent,
+    TelemetryPayload,
+    TelemetryResponse,
+    PostcheckAnswer,
+    CompleteSessionRequest,
+    SessionSummaryResponse,
+    UnitListItem,
+    RecommendedUnit,
+    CreateUnitRequest,
+    UpdateUnitRequest,
+    ValidationError,
+    ValidationResult,
+)
+
+# Re-export helpers for any direct importers
+from .helpers import (  # noqa: F401
+    get_optional_current_user,
+    get_unit_database,
+    create_session_token,
+    verify_session_token,
+    get_session_from_token,
+    validate_unit_definition,
+    USE_DATABASE,
+    REQUIRE_AUTH,
+    SECRET_KEY,
+)
+
+# Assemble the combined router.
+# _routes_router and _content_router both use prefix="/api/units",
+# so we create a plain router and include them without extra prefix.
+router = APIRouter()
+router.include_router(_routes_router)
+router.include_router(_definition_router)
+router.include_router(_content_router)