feat: verify_l1_address

[noa-starkware]

This change is 

[remollemo]

@remollemo reviewed all commit messages.
Reviewable status: 0 of 3 files reviewed, 1 unresolved discussion (waiting on @noa-starkware)

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packages/usdc_migration/src/usdc_migration.cairo line 92 at r1 (raw file):

        assert!(from_address == self.l1_recipient.read().into(), "{}", Error::VERIFY_L1_FAILED);
        // TODO: Emit event?
    }

this would be unhelpful.
definitely without an event/

unlike the problem with l2 owner address where we want to be sure the owner is valid before we get money etc,
here it's easier, as we are not forced into a state.

so - we can simply condition the operation - migration, send to l1 whatever, with the l1 address been validated.

dont revert.
when the address is correct - simply flag it as so.
and condition the actions on this flag.

Code quote:

    /// Verify the L1 recipient address is a reachable address.
    #[l1_handler]
    fn verify_l1_recipient(self: @ContractState, from_address: felt252) {
        assert!(from_address == self.l1_recipient.read().into(), "{}", Error::VERIFY_L1_FAILED);
        // TODO: Emit event?
    }

[noa-starkware]

Reviewable status: 0 of 3 files reviewed, 1 unresolved discussion (waiting on @noa-starkware and @remollemo)

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packages/usdc_migration/src/usdc_migration.cairo line 92 at r1 (raw file):

Previously, remollemo wrote…

this would be unhelpful.
definitely without an event/

unlike the problem with l2 owner address where we want to be sure the owner is valid before we get money etc,
here it's easier, as we are not forced into a state.

so - we can simply condition the operation - migration, send to l1 whatever, with the l1 address been validated.

dont revert.
when the address is correct - simply flag it as so.
and condition the actions on this flag.

Done.

[remollemo]

@remollemo reviewed 3 of 3 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @noa-starkware)

[remollemo]

Reviewable status: 2 of 3 files reviewed, 1 unresolved discussion (waiting on @noa-starkware)

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packages/usdc_migration/src/usdc_migration.cairo line 34 at r3 (raw file):

        /// The threshold amount of legacy token balance, that triggers sending to L1.
        legacy_threshold: u256,
        /// Whether the L1 recipient address is verified.

Suggestion:

/// Indicates if L1 recipient address was verified.

[remollemo]

@remollemo reviewed all commit messages.
Reviewable status: 1 of 3 files reviewed, 1 unresolved discussion (waiting on @noa-starkware)

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packages/usdc_migration/src/usdc_migration.cairo line 156 at r4 (raw file):

        self.l1_recipient_verified.write(true);
        // TODO: Emit event?
    }

1. i don't think there is a reason to revert
2. once we've successfully validated the l1 recipient reverting with failed to verify l1 recipient is really confusing.
3. yeah, i'd event this.
4. maybe smt like this:

Suggestion:

    fn verify_l1_recipient(ref self: ContractState, from_address: felt252) {
        if (! self.l1_recipient_verified.read() {
            l1_recipient: EthAddresss = self.l1_recipient.read();
            if (from_address == l1_recipient.into()) {
                self.l1_recipient_verified.write(true);
                self.emit(L1RecipientValidated { :l1_recipient });
            }
        }
    }