refactor: streamline HTML structure and enhance UI components

- Cleaned up the HTML structure in index.html and pdf-multi-tool.html for better readability and maintainability.
- Improved the user interface of the PDF multi-tool with responsive button designs and better layout.
- Added new CSS styles for button states and cursor behavior.
- Updated README with corrected Docker deployment link.
- Refactored JavaScript logic to utilize new helper functions for formatting star counts.
- Commented out unused attachment functionalities in the logic files for future integration.

src/css/styles.css

@@ -510,3 +510,14 @@ details > summary .icon {
 details[open] > summary .icon {
   transform: rotate(45deg);
 }
+
+button,
+.btn,
+.btn-gradient {
+  cursor: pointer;
+}
+
+button:disabled,
+.btn:disabled {
+  cursor: not-allowed;
+}