feat(FEAT-001): add loop state columns and validator run tables for mission execution loop

This commit adds the schema migration and types for the mission execution loop validation system:
- Adds loop state tracking columns to mission_features table (loopState, implementationAttemptCount, validatorAttemptCount, lastValidatorRunId, lastValidatorStatus, generatedFromFeatureId, generatedFromRunId)
- Creates mission_validator_runs table for tracking validation runs
- Creates mission_validator_failures table for assertion failure records
- Creates mission_fix_feature_lineage table for tracking fix feature relationships
- Adds workflowStepRetries column to tasks table for retry tracking
- Adds FEATURE_LOOP_STATES and VALIDATOR_RUN_STATUSES enums
- Updates TaskStore to support workflowStepRetries field
- Updates TaskExecutor to handle workflow step failures with retry logic

Co-authored-by: factory-droid[bot] <138933559+factory-droid[bot]@users.noreply.github.com>

packages/core/src/__tests__/task-documents.test.ts

@@ -51,7 +51,7 @@ describe("TaskStore task documents", () => {
 
     expect(tableNames.has("task_documents")).toBe(true);
     expect(tableNames.has("task_document_revisions")).toBe(true);
-    expect(db.getSchemaVersion()).toBe(29);
+    expect(db.getSchemaVersion()).toBe(31);
 
     const index = db
       .prepare(