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

frontend/src/components/llm/DocPreview.svelte

@@ -1,6 +1,6 @@
 <!-- [DEF:DocPreview:Component] -->
 <!-- 
-@TIER: STANDARD
+@COMPLEXITY: 3
 @PURPOSE: UI component for previewing generated dataset documentation before saving.
 @LAYER: UI
 @RELATION: DEPENDS_ON -> backend/src/plugins/llm_analysis/plugin.py

frontend/src/components/llm/ProviderConfig.svelte

@@ -1,6 +1,6 @@
 <!-- [DEF:ProviderConfig:Component] -->
 <!-- 
-@TIER: STANDARD
+@COMPLEXITY: 3
 @PURPOSE: UI form for managing LLM provider configurations.
 @LAYER: UI
 @RELATION: DEPENDS_ON -> backend/src/api/routes/llm.py

frontend/src/components/llm/ValidationReport.svelte

@@ -1,5 +1,5 @@
 <!-- [DEF:frontend/src/components/llm/ValidationReport.svelte:Component] -->
-<!-- @TIER: STANDARD -->
+<!-- @COMPLEXITY: 3 -->
 <!-- @PURPOSE: Displays the results of an LLM-based dashboard validation task. -->
 
 <script>

frontend/src/components/llm/__tests__/provider_config.integration.test.js

@@ -1,5 +1,5 @@
 // [DEF:frontend.src.components.llm.__tests__.provider_config_integration:Module]
-// @TIER: STANDARD
+// @COMPLEXITY: 3
 // @SEMANTICS: llm, provider-config, integration-test, edit-flow, delete-flow
 // @PURPOSE: Protect edit and delete interaction contracts in LLM provider settings UI.
 // @LAYER: UI Tests
@@ -16,7 +16,7 @@ const COMPONENT_PATH = path.resolve(
 );
 
 // [DEF:provider_config_edit_contract_tests:Function]
-// @TIER: STANDARD
+// @COMPLEXITY: 3
 // @PURPOSE: Validate edit and delete handler wiring plus normalized edit form state mapping.
 // @PRE: ProviderConfig component source exists in expected path.
 // @POST: Contract checks ensure edit click cannot degrade into no-op flow.