Plugin-Skill

Build, test, sign, and publish plugins for TREK, the self-hosted travel planner (github.com/liketrek/TREK). Covers the trek-plugin.json manifest, the definePlugin server API and ctx object, the sandboxed iframe postMessage bridge for widget/page UIs, permissions and egress rules, the enforced `trek` TREK-version range, local development with trek-plugin-sdk (create/dev/status/shot/validate/pack), author signing (keygen/--sign, Ed25519 trust-on-first-use), and publishing to the TREK-Plugins community registry including every CI gate. Use when creating or modifying a TREK plugin, working with trek-plugin-sdk or trek-plugin.json, signing a plugin or handling a signature/key-rotation problem (SIGNATURE_KEY_CHANGED, re-trust, allow-key-change), debugging PERMISSION_DENIED / RESOURCE_FORBIDDEN / TREK_VERSION_INCOMPATIBLE / TREK_VERSION_UNKNOWN or a plugin that will not install or activate on a given TREK version, or preparing a TREK-Plugins registry entry or PR.