feat: add PendingRewardDialog, RewardConfirmDialog, and TaskConfirmDialog components

- Implemented PendingRewardDialog for handling pending reward requests.
- Created RewardConfirmDialog for confirming reward redemption.
- Developed TaskConfirmDialog for task confirmation with child name display.

test: add unit tests for ChildView and ParentView components

- Added comprehensive tests for ChildView including task triggering and SSE event handling.
- Implemented tests for ParentView focusing on override modal and SSE event management.

test: add ScrollingList component tests

- Created tests for ScrollingList to verify item fetching, loading states, and custom item classes.
- Included tests for two-step click interactions and edit button display logic.
- Moved toward hashed passwords.

backend/api/error_codes.py

@@ -11,4 +11,18 @@ MISSING_EMAIL_OR_PASSWORD = "MISSING_EMAIL_OR_PASSWORD"
 INVALID_CREDENTIALS = "INVALID_CREDENTIALS"
 NOT_VERIFIED = "NOT_VERIFIED"
 ACCOUNT_MARKED_FOR_DELETION = "ACCOUNT_MARKED_FOR_DELETION"
-ALREADY_MARKED = "ALREADY_MARKED"
+ALREADY_MARKED = "ALREADY_MARKED"
+
+
+class ErrorCodes:
+    """Centralized error codes for API responses."""
+    UNAUTHORIZED = "UNAUTHORIZED"
+    CHILD_NOT_FOUND = "CHILD_NOT_FOUND"
+    TASK_NOT_FOUND = "TASK_NOT_FOUND"
+    REWARD_NOT_FOUND = "REWARD_NOT_FOUND"
+    ENTITY_NOT_ASSIGNED = "ENTITY_NOT_ASSIGNED"
+    OVERRIDE_NOT_FOUND = "OVERRIDE_NOT_FOUND"
+    MISSING_FIELD = "MISSING_FIELD"
+    INVALID_VALUE = "INVALID_VALUE"
+    VALIDATION_ERROR = "VALIDATION_ERROR"
+    INTERNAL_ERROR = "INTERNAL_ERROR"