fix(tests): resolve AmbiguousStep conflict and robot helper import path

Three issues causing CI failures in advanced-context-strategies tests:

1. AmbiguousStep: `@then("the strategy should be {strategy_type}")` in
   advanced_context_strategies_steps.py conflicted with the existing
   `@then('the strategy should be "{expected_strategy}"')` in
   plan_merge_strategy_steps.py:122. Renamed to
   `@then("the loaded strategy type should be {strategy_type}")` and
   updated all four matching lines in the feature file.

2. Wrong fragment count assertion: scenario "Semantic search strategy
   ranks by embedding similarity" expected 3 fragments but
   SemanticEmbeddingStrategy (word-overlap Jaccard, min_similarity=0.05)
   correctly filters "File input output handler" (0 overlap with
   "database connection"). Fixed assertion from 3 to 2.

3. Robot helper import failure: `features.mocks` is not importable when
   Robot Framework imports the library because it adds robot/ to
   sys.path but not the project root. Added explicit project-root
   sys.path.insert before the features.mocks import (same pattern as
   helper_lsp_stub.py), with # noqa: E402 on the post-path imports.

ISSUES CLOSED: #7574

features/advanced_context_strategies.feature

@@ -19,7 +19,7 @@ Feature: Advanced Context Strategies Integration Tests
     And a context budget with max_tokens 1000 and reserved_tokens 0
     When I search with query "database connection"
     Then the first result should have uko_node "project://app/db.py"
-    And the result should have 3 fragments
+    And the result should have 2 fragments
 
   @semantic_search
   Scenario: Semantic search filters low-similarity results
@@ -169,27 +169,27 @@ Feature: Advanced Context Strategies Integration Tests
   Scenario: Load semantic search strategy from YAML
     Given a YAML policy with semantic search configuration
     When I load the strategy from YAML
-    Then the strategy should be "semantic-embedding"
+    Then the loaded strategy type should be "semantic-embedding"
     And the strategy should have min_similarity configured
 
   @yaml_config
   Scenario: Load relevance scoring strategy from YAML
     Given a YAML policy with relevance scoring configuration
     When I load the strategy from YAML
-    Then the strategy should be "relevance-scoring"
+    Then the loaded strategy type should be "relevance-scoring"
 
   @yaml_config
   Scenario: Load adaptive selector from YAML
     Given a YAML policy with adaptive selector configuration
     When I load the strategy from YAML
-    Then the strategy should be "adaptive-selector"
+    Then the loaded strategy type should be "adaptive-selector"
     And the strategy should have fallback strategy configured
 
   @yaml_config
   Scenario: Load context fusion from YAML
     Given a YAML policy with context fusion configuration
     When I load the strategy from YAML
-    Then the strategy should be "context-fusion"
+    Then the loaded strategy type should be "context-fusion"
     And the strategy should have multiple strategies configured
 
   @yaml_config

features/steps/advanced_context_strategies_steps.py

@@ -402,7 +402,7 @@ def step_selected_strategy(context: Context, strategy_name: str) -> None:
     assert context.selected_name == expected
 
 
-@then("the strategy should be {strategy_type}")
+@then("the loaded strategy type should be {strategy_type}")
 def step_loaded_strategy_type(context: Context, strategy_type: str) -> None:
     """Check loaded strategy type."""
     expected = strategy_type.strip('"')

robot/helper_advanced_context_strategies.py

@@ -2,19 +2,28 @@
 
 from __future__ import annotations
 
+import sys
+from pathlib import Path
 from typing import Any
 
-from features.mocks.advanced_context_strategies_mocks import (
+# Robot Framework adds the library file's directory (robot/) to sys.path, but
+# features.mocks lives at the project root. Insert the project root so the
+# import below resolves correctly regardless of invocation context.
+_PROJECT_ROOT = str(Path(__file__).resolve().parents[1])
+if _PROJECT_ROOT not in sys.path:
+    sys.path.insert(0, _PROJECT_ROOT)
+
+from features.mocks.advanced_context_strategies_mocks import (  # noqa: E402
     AdaptiveContextSelector,
     ContextFusionStrategy,
     RelevanceScoringStrategy,
 )
 
-from cleveragents.application.services.context_strategies import (
+from cleveragents.application.services.context_strategies import (  # noqa: E402
     BreadthDepthNavigatorStrategy,
     SemanticEmbeddingStrategy,
 )
-from cleveragents.domain.models.core.context_fragment import (
+from cleveragents.domain.models.core.context_fragment import (  # noqa: E402
     ContextBudget,
     ContextFragment,
     FragmentProvenance,