Epic: 020-extensibility (v3.0)

[ichinya]

Goal

Open the core for controlled extensibility.

Scope

• define plugin and extension contracts
• support local-model or custom-provider adapters
• keep extension points versioned and testable
• preserve core ownership of domain invariants

Done When

• new providers can be integrated without rewriting the core
• plugin compatibility rules are explicit
• extension paths do not break existing contract consumers

Dependencies

Blocked by

• Epic: 014-proxy-mode (v2.1) #8
• Epic: 017-web-panel (v2.4) #9

Enables

• Epic: 030-infrastructure (v4.0) #13

Cross-repo / version gate

• Extensibility opens only after proxy and web-facing contract surfaces stabilize.