refactor(semantics): migrate legacy @TIER to @COMPLEXITY annotations

- Replaced @TIER: TRIVIAL with @COMPLEXITY: 1
- Replaced @TIER: STANDARD with @COMPLEXITY: 3
- Replaced @TIER: CRITICAL with @COMPLEXITY: 5
- Manually elevated specific critical/complex components to levels 2 and 4
- Ignored legacy, specs, and node_modules directories
- Updated generated semantic map

backend/src/api/routes/migration.py

@@ -1,5 +1,5 @@
 # [DEF:backend.src.api.routes.migration:Module]
-# @TIER: CRITICAL
+# @COMPLEXITY: 5
 # @SEMANTICS: api, migration, dashboards, sync, dry-run
 # @PURPOSE: HTTP contract layer for migration orchestration, settings, dry-run, and mapping sync endpoints.
 # @LAYER: Infra
@@ -38,7 +38,7 @@ from ...models.mapping import ResourceMapping
 router = APIRouter(prefix="/api", tags=["migration"])
 
 # [DEF:get_dashboards:Function]
-# @TIER: STANDARD
+# @COMPLEXITY: 3
 # @PURPOSE: Fetch dashboard metadata from a requested environment for migration selection UI.
 # @PRE: env_id is provided and exists in configured environments.
 # @POST: Returns List[DashboardMetadata] for the resolved environment; emits HTTP_404 when environment is absent.
@@ -66,7 +66,7 @@ async def get_dashboards(
 # [/DEF:get_dashboards:Function]
 
 # [DEF:execute_migration:Function]
-# @TIER: CRITICAL
+# @COMPLEXITY: 5
 # @PURPOSE: Validate migration selection and enqueue asynchronous migration task execution.
 # @PRE: DashboardSelection payload is valid and both source/target environments exist.
 # @POST: Returns {"task_id": str, "message": str} when task creation succeeds; emits HTTP_400/HTTP_500 on failure.
@@ -108,7 +108,7 @@ async def execute_migration(
 
 
 # [DEF:dry_run_migration:Function]
-# @TIER: CRITICAL
+# @COMPLEXITY: 5
 # @PURPOSE: Build pre-flight migration diff and risk summary without mutating target systems.
 # @PRE: DashboardSelection is valid, source and target environments exist, differ, and selected_ids is non-empty.
 # @POST: Returns deterministic dry-run payload; emits HTTP_400 for guard violations and HTTP_500 for orchestrator value errors.
@@ -160,7 +160,7 @@ async def dry_run_migration(
 # [/DEF:dry_run_migration:Function]
 
 # [DEF:get_migration_settings:Function]
-# @TIER: STANDARD
+# @COMPLEXITY: 3
 # @PURPOSE: Read and return configured migration synchronization cron expression.
 # @PRE: Configuration store is available and requester has READ permission.
 # @POST: Returns {"cron": str} reflecting current persisted settings value.
@@ -178,7 +178,7 @@ async def get_migration_settings(
 # [/DEF:get_migration_settings:Function]
 
 # [DEF:update_migration_settings:Function]
-# @TIER: STANDARD
+# @COMPLEXITY: 3
 # @PURPOSE: Validate and persist migration synchronization cron expression update.
 # @PRE: Payload includes "cron" key and requester has WRITE permission.
 # @POST: Returns {"cron": str, "status": "updated"} and persists updated cron value.
@@ -204,7 +204,7 @@ async def update_migration_settings(
 # [/DEF:update_migration_settings:Function]
 
 # [DEF:get_resource_mappings:Function]
-# @TIER: STANDARD
+# @COMPLEXITY: 3
 # @PURPOSE: Fetch synchronized resource mappings with optional filters and pagination for migration mappings view.
 # @PRE: skip>=0, 1<=limit<=500, DB session is active, requester has READ permission.
 # @POST: Returns {"items": [...], "total": int} where items reflect applied filters and pagination.
@@ -255,7 +255,7 @@ async def get_resource_mappings(
 # [/DEF:get_resource_mappings:Function]
 
 # [DEF:trigger_sync_now:Function]
-# @TIER: STANDARD
+# @COMPLEXITY: 3
 # @PURPOSE: Trigger immediate ID synchronization for every configured environment.
 # @PRE: At least one environment is configured and requester has EXECUTE permission.
 # @POST: Returns sync summary with synced/failed counts after attempting all environments.