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 DB support and migration, introduces malefactor banning, and refactors neighborhood initialization with broad test updates.

• Database:
  • Bump CURRENT_SCHEMA_VERSION to 12; add migration 11_to_12 inserting default rate_pack_limits.
  • Initialize and persist rate_pack_limits; update initializer and tests accordingly.
• Config/Runtime:
  • Add RatePackLimits and DEFAULT_RATE_PACK_LIMITS; validate RatePack on configuration and during gossip processing.
  • Extend PersistentConfiguration to read rate_pack_limits; add factory and "invalid" placeholders.
• Gossip/Neighborhood:
  • Introduce Malefactor type and switch ban path to carry structured data; handlers may return multiple results.
  • Validate incoming Debut/Introduction/Standard gossip against rate-pack limits; improve logging/formatting (Display for records, agrs_to_string).
  • Refactor neighborhood start-up to use PersistentConfigurationFactory and construct GossipAcceptor with limits.
• Tests/Integrations:
  • Update tests to new APIs, larger default rate-pack values, longer timeouts, and additional nodes; add new unit tests for limits and parsing.
  • Integration: remove existing Docker network before create.
• Misc:
  • Add time feature local-offset; minor renames/var tweaks; .gitignore adds Copilot files.

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