fix: resolve TypeScript typecheck errors in Phase 0 implementation

- Fix git-utils import in PreflightChecker using require() with type casting
- Fix ConfigManager initialization in TaskLoaderService (use async factory)
- Fix TaskService.getTask return type (returns Task | null directly)
- Export PreflightChecker and TaskLoaderService from @tm/core
- Fix unused parameter and type annotations in autopilot command
- Add boolean fallback for optional dryRun parameter

All turbo:typecheck errors resolved.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

packages/tm-core/src/index.ts

@@ -72,3 +72,14 @@ export {
 	type ComplexityAnalysis,
 	type TaskComplexityData
 } from './reports/index.js';
+
+// Re-export services
+export {
+	PreflightChecker,
+	TaskLoaderService,
+	type CheckResult,
+	type PreflightResult,
+	type TaskValidationResult,
+	type ValidationErrorType,
+	type DependencyIssue
+} from './services/index.js';