Standardized ?params to prefill correctly, resulting in API issues (eg, QR code SMS template)

• [x ] I have searched open and closed issues for duplicates
• [x ] I am submitting a bug report for existing functionality that does not work as intended
• [x ] I have read https://github.com/signalapp/Signal-Android/wiki/Submitting-useful-bug-reports
• [x ] This isn't a feature request or a discussion topic

Bug description

For example, Taiwan gov't COVID tracking program will need me to register via QR code (that submits a pre-filled text containing the identity of the venue):

The result is an empty text compose with a broken "to" field (I'll edit this later with a screenshot). Eg:

{smsNum}?body={body} : {realPhoneNumHere}{messageHere}

The actual message has 0 prefilled.

Steps to reproduce

1. Scan a QR code that has ?parameters to send a prefilled text message.
2. Watch the "to" field containing the entire API line.
3. Even if you filled the body and sent, it's still broken due to the to field being messed up.

Actual result:
Prefill params are all in the "to" area: Need to change default app to anything except Signal to work (it's just you guys that don't follow these standards, it appears).

Expected result:
Message should be prefilled as standardized.

Screenshots

TODO

Device info

Device: Samsung S20+
Android version: 11
Signal version: 5.15.6

Link to debug log

n/a

Start by reproducing the QR-code flow on Android 11 with Signal 5.15.6, using a URL with ?parameters as described in the steps. Trace the entry point that handles the link and verify that the recipient and message body are separated and prefilled according to the expected standard.