The SDK is the contract every other M7 story builds on (ADR 0008,
plugin-architecture.md). New package `@dorfteich/plugin-sdk`, standalone
(only depends on zod) so a plugin author needs nothing else.
- Zod manifest schema (`validateManifest`/`parseManifest`) with actionable
`{ path, message }` issues and cross-field rules (extension-point/kind
match, unique ids, section_style declares no permissions). Fixtures:
3 valid + 14 invalid variants, asserted individually.
- `checkApiVersion` compatibility helper against the host's supported range.
- Capability names + method→capability map as the single source of truth
for the permission gate.
- Transport-agnostic postMessage RPC engine (`createRpcEndpoint`) with
request/response ids, per-request timeouts, unknown-method and
endpoint-disposed handling, plus a `windowTransport` adapter.
- Host side (`createHostBridge`): routes plugin capability calls through
the manifest permission gate; drives plugin lifecycle (render/edit/destroy).
- Plugin side (`createPlugin`): answers lifecycle calls, exposes a typed
`host` proxy. RPC roundtrip verified in a jsdom MessageChannel test
(roundtrip, args, timeout, unknown method, undeclared capability, dispose).
- README documents the protocol with a mermaid sequence diagram.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EwZ4jR4KFAPvpjWevfUGX1
