Common origin when registering

[lmuntaner]

Motivation

Make sure that the metadata's origin matches the devices origin and the actual RP ID on the passkey manager (iCloud, 1Password, etc)

Changes

• Add an origin parameter to passkeyAuthnMethodData which creates the device's metadata.
• Add an origin parameter to savePasskeyOrPin and use it to calculate the RP ID for constructIdentity.
• Use a common variable to pass the same origin to passkeyAuthnMethodData and savePasskeyOrPin.

Tests

Tested in beta domains by creating one new identity in ic0.app and another in internetcomputer.org and checking that the origin matched the expected. Metadata is private data. I couldn't check that.

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🟡 Some screens were changed

[lmuntaner]

@sea-snake please review