Add Save as option for VIEW intents with content:// URIs

[SolsticeSpectrum]

Description

Adds "Save as" option when opening files via VIEW intent with content:// URIs.

Previously, when apps like Mattermost send a VIEW intent for a single file, users only saw "Amaze Document Viewer" which just prompts to download File Utilities. Now users will also see "Save as" option that triggers the existing save flow.

Automatic tests

• [ ] Added test cases

Manual tests

• [x] Done

• Device: Nothing Phone 2

• OS: Android 16

Build tasks success

Successfully running following tasks on local:

• [x] ./gradlew assembledebug
• [x] ./gradlew spotlessCheck