feat(06-01): add task_sessions CRUD, nativeContextManagement flag, TaskSessionRecord type

- Add getActiveTaskSession, incrementSessionUsage, archiveSession, createNewSession,
  getRecentRunsForTask, getRecentActivityForTask methods to AppDatabase
- Add nativeContextManagement optional boolean to ServerAdapterModule interface
- Set nativeContextManagement: true for claude_local and codex_local, false for gemini_local
- Add TaskSessionRecord interface to shared types
- Add unit tests for task_sessions CRUD and adapter exemption flags

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/adapter-utils/src/types.ts

@@ -179,6 +179,8 @@ export interface ServerAdapterModule {
   models?: AdapterModel[];
   listModels?: () => Promise<AdapterModel[]>;
   agentConfigurationDoc?: string;
+  /** Per D-04: If true, adapter manages its own context window (e.g. Claude, Codex). Session rotation is skipped but usage is still tracked. */
+  nativeContextManagement?: boolean;
   /**
    * Optional lifecycle hook when an agent is approved/hired (join-request or hire_agent approval).
    * adapterConfig is the agent's adapter config so the adapter can e.g. send a callback to a configured URL.