Refactor color input fields and enhance watermark functionality

- Updated color input fields in various HTML pages to remove unnecessary classes for improved styling consistency.
- Modified the watermark node to include options for positioning and flattening watermarks.
- Enhanced the addTextWatermark function to support customizable positioning and page selection for watermarks.
- Added new controls for text and image watermarks in the UI, allowing users to specify text, font size, color, opacity, angle, and image scaling.
- Updated the WASM provider to use the latest version of pymupdf-wasm.

src/pages/background-color.html

@@ -182,12 +182,7 @@
               class="block mb-2 text-sm font-medium text-gray-300"
               >Background Color</label
             >
-            <input
-              type="color"
-              id="background-color"
-              value="#FFFFCC"
-              class="w-full h-12 bg-gray-700 border border-gray-600 rounded-lg cursor-pointer"
-            />
+            <input type="color" id="background-color" value="#FFFFCC" />
           </div>
           <button id="process-btn" class="btn-gradient w-full mt-4">
             Change Background Color