skill: use Effect.cached for load deduplication

Author: kitlangton

packages/opencode/src/skill/index.ts

@@ -54,11 +54,10 @@ export namespace Skill {
   type State = {
     skills: Record<string, Info>
     dirs: Set<string>
-    task?: Promise<void>
   }
 
   type Cache = State & {
-    ensure: () => Promise<void>
+    load: () => Promise<void>
   }
 
   export interface Interface {
@@ -116,7 +115,6 @@ export namespace Skill {
       })
   }
 
-  // TODO: Migrate to Effect
   const create = (discovery: Discovery.Interface, directory: string, worktree: string): Cache => {
     const state: State = {
       skills: {},
@@ -166,16 +164,7 @@ export namespace Skill {
       log.info("init", { count: Object.keys(state.skills).length })
     }
 
-    const ensure = () => {
-      if (state.task) return state.task
-      state.task = load().catch((err) => {
-        state.task = undefined
-        throw err
-      })
-      return state.task
-    }
-
-    return { ...state, ensure }
+    return { ...state, load }
   }
 
   export class Service extends ServiceMap.Service<Service, Interface>()("@opencode/Skill") {}
@@ -188,12 +177,18 @@ export namespace Skill {
         Effect.fn("Skill.state")((ctx) => Effect.sync(() => create(discovery, ctx.directory, ctx.worktree))),
       )
 
-      const ensure = Effect.fn("Skill.ensure")(function* () {
+      const ensureCached = Effect.fnUntraced(function* () {
         const cache = yield* InstanceState.get(state)
-        yield* Effect.promise(() => cache.ensure())
+        yield* Effect.promise(() => cache.load())
         return cache
       })
 
+      let cachedEnsure = yield* Effect.cached(ensureCached())
+
+      const ensure = Effect.fn("Skill.ensure")(function* () {
+        return yield* cachedEnsure
+      })
+
       const get = Effect.fn("Skill.get")(function* (name: string) {
         const cache = yield* ensure()
         return cache.skills[name]