Use tx.from fallback to account in boopFromTransaction in iframe sendBoop func

[AryanGodara]

Description

Closes: HAPPY-552

Updated the boopFromTransaction function to use the provided account as a fallback when tx.from is not available. This ensures the function can handle transactions where the sender information might be missing.

I went through the surrounding code flow (from request handlers to utils inside iframe/src/requests). But I couldn't find any other thing which had to be tweaked, as there was no description for the linear issue, only title 😅

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[AryanGodara]

• Use tx.from fallback to account in boopFromTransaction in iframe sendBoop func #790 👈 (View in Graphite)
• master

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[linear]

HAPPY-552 make `from` in sendBoop tx arg optional again (session key functions)

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[norswap]

Because of how parseBigInt (one of our utility function) works, all of these can be parseBigInt(thing) ?? fallback — I actually completely coincidentally made the change in the PR I'm working on, so this can stay like this.