refactor(SensorsBlocks): remove duplicate methods and consolidate pixel data handling

- Removed duplicate getPixelDataFromMedia method
- Merged pixel data handling into unified getPixelData method
- Updated arg method to use the consolidated getPixelData
- Improved error handling and documentation
- Fixed RGB component indexing in GetBlueBlock and GetGreenBlock
- Made code more maintainable and DRY

This change eliminates code duplication while preserving all functionality
and improving error handling across the SensorsBlocks implementation.

Author: Adityacode-hub

js/blocks/SensorsBlocks.js

@@ -999,8 +999,8 @@ class GetColorMediaBlock extends ValueBlock {
      */
     /**
      * Gets pixel color data from either the canvas or a media block.
-     * @param {number} x - The x-coordinate of the pixel.
-     * @param {number} y - The y-coordinate of the pixel.
+     * @param {number} x - The x-coordinate of the pixel to sample.
+     * @param {number} y - The y-coordinate of the pixel to sample.
      * @param {Object} [mediaBlock] - Optional media block to read from.
      * @returns {Uint8ClampedArray} - The RGBA values of the pixel.
      * @throws {Error} - If the canvas context is unavailable or media access fails.