Refactor: unify dialog styles across components

- Add unified .dialog-overlay and .dialog classes to tailwind.css
- Remove duplicated dialog styles from 9 Vue components
- Standardize z-index to 50 for all dialogs
- Preserve special cases: FeedFilters (z-index: 100), PhotoDialog (camera styles)
- Eliminate ~200 lines of duplicated CSS code
- Updated ContactNameDialog from using getter methods to direct CSS classes
- Improve maintainability with single source of truth for dialog styling

src/assets/styles/tailwind.css

@@ -14,4 +14,12 @@
 		transform: translateX(100%);
 		background-color: #FFF !important;
 	}
+
+	.dialog-overlay {
+		@apply z-50 fixed inset-0 bg-black/50 flex justify-center items-center p-6;
+	}
+
+	.dialog {
+		@apply bg-white p-4 rounded-lg w-full max-w-lg;
+	}
 }