5.2 Implement BP-ARP subsystem

[ricktaylor]

Generic EID resolution for Neighbours.

Design

• Subscribes to Neighbour notifications from CLAs
• For each Neighbour without EID: send BP-ARP probe
• On response: install 1-hop route in RIB
• On failure (retries exhausted): log, no route installed
• Neighbour lifecycle is CLA-managed (CLA adds/removes)

Configurable

• probe_interval
• retry_count

References

• TODO.md Section 5
• bpa/docs/bp_arp_design.md

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Blocked by: #361