Support scanning SeedQR recovery phrases

Blockstream Wallet's QR scanner only reads a recovery phrase as plain text words. It doesn't recognize SeedQR, the standard format for encoding a recovery phrase as a QR code, which Jade itself can already create and scan.

Scanning one on the restore screen currently does nothing at all. No error, no message, so it just looks broken. This was first noticed on iOS.

Could Blockstream Wallet accept SeedQR (ideally CompactSeedQR too)? And in the meantime, show a message for unrecognized QR codes instead of ignoring them.

Same request as Blockstream/green_android#311, filed separately here because the iOS app has its own scanning code.

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_{Filed by my AI agent on my behalf.}