Allow install/storage on SDcard

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Is there an existing request for this?

• I have searched the existing issues

Feature description

As the client persistently stores all relevant content locally, it tends to fill up the internal storage quickly.
Some another messengers and apps offer the option to either install or store content onto an SDcard.

As mentioned in the Signal Form, one flag in the manifest has to be added. However according to the android docs, linked from there, a service can be hindered when installed on the SDcard, which might effect things like notification handling on Molly-FOSS.

On Telegram, one cannot install on the sdcard but there is an option in settings for content to be stored on such external storage. However, this implementation might require more code changes in how the app stores content.

Could a feature like this be added to Molly?