fix: Improve error handling and test coverage before npm publish

- Fixed getFrame() to return undefined instead of throwing errors
- Updated error handling tests to use correct StackMemoryError constructor
- Removed dangerous secret-cleaning scripts from repository
- All tests passing, lint clean, build successful

Author: jonathanpeterwu

src/core/context/frame-database.ts

@@ -155,12 +155,8 @@ export class FrameDatabase {
         digest_json: JSON.parse(row.digest_json || '{}'),
       };
     } catch (error: unknown) {
-      throw new DatabaseError(
-        `Failed to get frame: ${frameId}`,
-        ErrorCode.DB_QUERY_FAILED,
-        { frameId, operation: 'getFrame' },
-        error instanceof Error ? error : undefined
-      );
+      logger.warn(`Failed to get frame: ${frameId}`, { error });
+      return undefined;
     }
   }
 

src/core/errors/__tests__/error-handling.test.ts

@@ -7,14 +7,18 @@ import { StackMemoryError, ErrorCode } from '../index.js';
 
 describe('Error System', () => {
   it('should create StackMemoryError', () => {
-    const error = new StackMemoryError('Test error', ErrorCode.VALIDATION_FAILED);
+    const error = new StackMemoryError({
+      message: 'Test error',
+      code: ErrorCode.VALIDATION_FAILED
+    });
 
     expect(error).toBeInstanceOf(Error);
-    expect(error.code).toBeDefined();
+    expect(error.message).toBe('Test error');
+    expect(error.name).toBe('StackMemoryError');
   });
 
   it('should handle error codes', () => {
-    expect(ErrorCode.VALIDATION_FAILED).toBeDefined();
-    expect(ErrorCode.NETWORK_ERROR).toBeDefined();
+    expect(ErrorCode.VALIDATION_FAILED).toBe('VAL_001');
+    expect(ErrorCode.DB_CONNECTION_FAILED).toBe('DB_001');
   });
 });