fix(context): resolve PR #10590 review blockers and compliance items

- Move DomainContextStrategy / DomainStrategyCapabilities to TYPE_CHECKING block in acms_service.py (lint F401)
- Deduplicate CHANGELOG.md ### Added sections under [Unreleased]
- Remove duplicate CONTRIBUTORS.md entry for ContextStrategy feature
- Ensure security scan compatibility

ISSUES CLOSED: #8616, #10590

CHANGELOG.md

@@ -5,7 +5,6 @@ The format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 ## [Unreleased]
 
-
 ### Added
 
 - **ContextStrategy Protocol and Plugin Registration System** (#10590): Implemented the
@@ -24,8 +23,6 @@ The format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
   MappingProxyType coercion validators, thread-safety under concurrent access, boundary value
   validation via Pydantic model constraints, and per-strategy config updates.
 
-### Added
-
 - **ContextStrategy protocol and StrategyRegistry plugin registration system** (#8616): Implemented the pluggable context assembly strategy protocol (`ContextStrategy`) with proper type-safe method signatures (`can_handle(request, backends) -> confidence`, `assemble(request, backends, budget, plan_context) -> fragments`). Added `StrategyRegistry` -- the central thread-safe registry for registration, lookup, discovery (via entry points), and per-strategy configuration (`timeout_seconds`, `max_fragments`, `max_workers`, `circuit_breaker_threshold`, `resource_types`, `extra`). Six built-in strategies implemented per spec: `simple-keyword` (0.3), `semantic-embedding` (0.6), `breadth-depth-navigator` (0.85), `arce` (0.95 -- multi-modal text+vector+graph), `temporal-archaeology` (0.5 -- historical discovery), and `plan-decision-context` (0.7 -- parent plan decision retrieval). Full BDD test coverage validating protocol conformance, registry CRUD operations, entry-point discovery, error handling, thread safety, and boundary validation.
 
 - Fixed `ReactiveEventBus.emit()` exception handler to log the full exception

CONTRIBUTORS.md

@@ -37,4 +37,3 @@ Below are some of the specific details of various contributions.
 * HAL 9000 has contributed the ACMS Index Data Model and File Traversal Engine (PR #9664 / issue #9579): foundational data structures for indexed context entries with hot/warm/cold/archive storage tier classification, tag system, and a timeout-safe chunked file traversal engine for large projects with 10,000+ files.
 * HAL 9000 has contributed the error-suppression removal fix (PR #9247 / issue #9060): removed both `try...except Exception:` blocks in `register_registry_agents()` that silently suppressed errors from `actor_registry.list_actors()` and the route bridge refresh, enabling exceptions to propagate per CONTRIBUTING.md fail-fast policy. Added three Behave scenarios verifying RuntimeError, AttributeError, and TypeError propagation.
 * HAL 9000 has contributed the Strategize phase full context snapshot fix (issue #9056): added `_build_strategize_context_snapshot()` helper to `PlanLifecycleService`, updated `_try_record_decision()` to accept and forward a `ContextSnapshot` parameter, and added BDD test coverage verifying all four `ContextSnapshot` fields (`hot_context_hash`, `hot_context_ref`, `actor_state_ref`, `relevant_resources`) are populated during the Strategize phase.
-* HAL 9000 has contributed the ContextStrategy protocol and plugin registration system (PR #10590): implemented the \`ContextStrategy\` protocol for the ACMS with six built-in strategies (SimpleKeyword, SemanticEmbedding, BreadthDepthNavigator, ARCE, TemporalArchaeology, PlanDecisionContext), a thread-safe StrategyRegistry supporting enable/disable configuration, per-strategy config updates, plugin discovery from module paths with allowlist security, validation warnings, and 77 Behave test scenarios covering all features.

src/cleveragents/application/services/acms_service.py

@@ -32,16 +32,16 @@ import structlog
 
 if TYPE_CHECKING:
     from cleveragents.config.settings import Settings
+    from cleveragents.domain.models.acms.strategy import (
+        ContextStrategy as DomainContextStrategy,
+        StrategyCapabilities as DomainStrategyCapabilities,
+    )
     from cleveragents.infrastructure.database.unit_of_work import UnitOfWork
     from cleveragents.infrastructure.plugins.manager import PluginManager
 
 from cleveragents.domain.models.acms.crp import (
     ContextRequest,
 )
-from cleveragents.domain.models.acms.strategy import (
-    ContextStrategy as DomainContextStrategy,
-    StrategyCapabilities as DomainStrategyCapabilities,
-)
 from cleveragents.domain.models.core.context_fragment import (
     ULID_PATTERN,
     ContextBudget,