mobile: initialize rustls provider before bridge startup

[saintmob]

Summary

• Install the process-wide rustls crypto provider from the shared mobile init path so iOS/Android bridge construction cannot hit the Rustls 0.23 provider panic.
• Keep MobileClient::new() as a second line of defense.
• Add the shared workspace dependency needed by the mobile Rust crate.

Verification

• Rebuilt the iPhone target after the Rust init fix.
• Confirmed the app launches successfully on a real iPhone.

Scope

• This PR intentionally includes only the mobile Rustls startup fix.
• It does not include unrelated local edits or the separate websocket token/logging follow-up.

[saintmob]