ZEBRA is a Zcash node written entirely in Rust. Prior to 4.5.0, an unauthenticated IPv4 peer can deterministically terminate a synced Zebra node using the default Linux dual-stack listener configuration. The handshake path canonicalized an IPv4-mapped IPv6 PeerSocketAddr such as ::ffff:127.0.0.1 to plain IPv4 before storing it through MetaAddr::new_connected, but the mempool misbehavior path forwarded the raw transient address to MetaAddrChange::UpdateMisbehavior. In zebra-network/src/meta_addr.rs, apply_to_meta_addr then compared the canonical address-book entry with the raw update address and reached its unexpected address mismatch assertion. After the misbehavior batch flush, panic equals abort terminated zebrad; the peer only needed to complete a P2P handshake and advertise an invalid mempool transaction. This issue is fixed in version 4.5.0.

Affected: crates.io: zebra-network, crates.io: zebrad

### Am I affected

You are affected if:

1. You run `zebrad` up to and including `v4.4.1`. 2. Your node listens on the default `[::]` address on a Linux host (the standard deployment configuration — `net.ipv6.bindv6only=0` is the default on all common Linux distributions). 3. Your node is synced near the chain tip (the expected production state for any node participating in the network).

### Summary

An address normalization mismatch between the handshake path and the mempool misbehavior path causes a deterministic assertion panic when a peer connects via IPv4 to a dual-stack IPv6 listener and then triggers a mempool misbehavior penalty.

The handshake path canonicalizes IPv4-mapped IPv6 addresses to plain IPv4 when storing the peer in the address book via `MetaAddr::new_connected`. The mempool misbehavior path forwards the raw transient socket address (IPv4-mapped IPv6 form) when sending `MetaAddrChange::UpdateMisbehavior` to the address book. The address book looks up the canonical IPv4 entry but then asserts that the previous entry's address matches the change's address. The mismatch between the canonical IPv4 address and the raw IPv4-mapped IPv6 address triggers the assertion, and `panic = "abort"` terminates the process.

### Details

On Linux with `net.ipv6.bindv6only=0`, an IPv4 connection accepted by a `[::]` listener is represented internally as an IPv4-mapped IPv6 socket address (e.g., `::ffff:127.0.0.1:8233`). Zebra's `canonical_peer_addr` helper converts these t…