feat(notes): enhance FollowupDate updates with logging and error handling

.gitconfig/CUSTOMER_NOTES_FOLLOWUP_IMPLEMENTATION.md

@@ -75,7 +75,7 @@ When an existing customer note is updated via `PUT /api/v1/notes/customers/{cust
 
 **Transaction Steps**:
 1. Update the note fields in `CustomerNotes` table
-2. If the note update was successful, **UPDATE** the customer's `FollowupDate` to current time
+2. If the note update was successful, **UPDATE** the customer's `FollowupDate` to the UI-provided date (or current time if not provided)
 3. Commit both operations as a single transaction
 
 **SQL Operations**:
@@ -86,7 +86,7 @@ WHERE NoteID2 = :note_id2 AND CustomerID = :customer_id;
 
 -- Update customer FollowupDate (if note was updated)
 UPDATE Customers 
-SET FollowupDate = GETDATE() 
+SET FollowupDate = :followup_date 
 WHERE CustomerID = :customer_id;
 ```