GH-686 Don't allow extreme rate packs; reject Gossip about extreme rate packs

[dnwiebe]

Note

Enforces rate-pack limits in config and gossip, adds malefactor banning, and bumps DB schema to v12 with new rate_pack_limits.

• DB/Config:
  • Bump schema to v12; add migration 11→12 inserting default rate_pack_limits.
  • Initialize/persist rate_pack_limits in db_initializer, config_dao_null, and factory plumbing.
  • Parse/validate rate_pack_limits from CONFIG; add regex-based parsing and guards.
• Rate Pack Limits:
  • Introduce RatePackLimits (+ defaults) and validation helpers; enforce in CLI --rate-pack via configurator.
• Gossip/Neighborhood:
  • Validate incoming Gossip (Debut/Introduction/Standard) against RatePackLimits; reject and emit Ban for violations.
  • Add Malefactor model and switch GossipAcceptanceResult::Ban to carry it; handlers now return Vec<GossipAcceptanceResult>; remove explicit Ignored (use empty vec).
  • Add GossipAcceptorInvalid/PersistentConfigurationInvalid and a real PersistentConfigurationFactory; wire into Neighborhood startup.
• Tests/Infra:
  • Update tests for new limits, API changes, and scaled rate-pack values; add new unit tests.
  • time crate adds local-offset; minor docker network cleanup; ignore .idea/copilot.*.

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