feat: add input stream as optional parameter to be loaded instead of …

[LucileSchneider]

Add an optional (nullable) InputStream parameter to the generated composable.
If this InputStream is provided, the dcf will be loaded from it with priority, before attempting to locate it in the app resources or assets.

An example implementation can be found in the hello world reference app. It canbe tested it by pushing the corresponding dcf file to the app dir:
adb push HelloWorldDoc_pxVlixodJqZL95zo2RzTHl.dcf /data/user/10/com.android.designcompose.testapp.helloworld/files

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