[vector_graphics] Fix raster cache size calculation and incorporate ColorFilter/Opacity effects into cache

[gaodi-sec]

This PR fixes the bugs mentioned in #8932.

1. The raster cache size generated by vector_graphics takes BoxFit into account but does not consider the impact of the Transform widget. In practice, the raster cache size can be derived directly from the canvas's scale, which naturally reflects all visual transformations—including BoxFit, Transform, and any other factors affecting the final display size of the component. This PR replaces the previous size calculation with one based on the canvas scale.

2. Currently, the raster cache does not include ColorFilter or Opacity, meaning that rendering overhead remains high when either is present, due to the need for additional offscreen rendering passes. However, in real-world scenarios—especially when using SVG assets—it's very common to apply ColorFilter for tinting. This PR incorporates ColorFilter and Opacity effects into the raster cache, reducing the overall rendering cost.

Of course, this PR also aims to address issue #166184.

Regarding point 2, before applying the fix, the trace output was as follows:

At that time, two SVGs were causing two vkQueueSubmit calls, resulting in two offscreen renderings, which took approximately 2ms.

After the fix, the trace output is as follows:

The vkQueueSubmit calls are no longer present, and the processing time has decreased to 0.6ms.

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