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/git_schemas.py

@@ -1,6 +1,6 @@
 # [DEF:backend.src.api.routes.git_schemas:Module]
 #
-# @TIER:      STANDARD
+# @COMPLEXITY: 3
 # @SEMANTICS: git, schemas, pydantic, api, contracts
 # @PURPOSE:   Defines Pydantic models for the Git integration API layer.
 # @LAYER:     API
@@ -14,7 +14,7 @@ from datetime import datetime
 from src.models.git import GitProvider, GitStatus, SyncStatus
 
 # [DEF:GitServerConfigBase:Class]
-# @TIER: TRIVIAL
+# @COMPLEXITY: 1
 # @PURPOSE: Base schema for Git server configuration attributes.
 class GitServerConfigBase(BaseModel):
     name: str = Field(..., description="Display name for the Git server")