firebase_ui_oauth: Pre-compile svg icon assets using `vector_graphics_compiler`

[lesnitsky]

Discussed in #240

^{Originally posted by aebrahim January 4, 2024}
The social login icons are packaged as strings containing the raw svg, which are then rendered using flutter_svg. However, under the hood, using flutter_svg means also including its dependency vector_graphics_compiler with the application, which at runtime converts raw svg to a compiled VectorGraphic to display.

Given that the svg string is known at build time, it is possible to pre-compile it as a VectorGraphic at build time. Advantages:

1. Would no longer pull in the vector_graphics_compiler dependency, which adds ~180 KB to the build.
2. Slightly more efficient runtime as the precompiled VectorGraphic can be a const.

[github-actions]

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This issue has been automatically marked as stale because it has not had activity for quite some time. Has this issue been fixed, or does it still require attention?

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[aebrahim]

This issue still requires attention - flutter_svg is still listed as a dependency at the current version here: https://github.com/firebase/FirebaseUI-Flutter/blob/93bfe605d9b45fe14c2b7a37567618d88e7f49b2/packages/firebase_ui_oauth/pubspec.yaml

[github-actions]

Hello 👋, to help manage issues we automatically close stale issues.

This issue has been automatically marked as stale because it has not had activity for quite some time. Has this issue been fixed, or does it still require attention?

This issue will be closed in 15 days if no further activity occurs.

Thank you for your contributions.