refactor(tool): convert multiedit tool to Tool.defineEffect

Migrate MultiEditTool from Tool.define to Tool.defineEffect pattern,
resolving EditTool via Effect.gen + Tool.init in the outer generator
and using Effect.promise + Effect.orDie in the execute body.

packages/opencode/src/tool/multiedit.ts

@@ -4,10 +4,9 @@ import { EditTool } from "./edit"
 import DESCRIPTION from "./multiedit.txt"
 import path from "path"
 import { Instance } from "../project/instance"
+import { Effect } from "effect"
 
-export const MultiEditTool = Tool.define("multiedit", {
+const Parameters = z.object({
-  description: DESCRIPTION,
-  parameters: z.object({
   filePath: z.string().describe("The absolute path to the file to modify"),
   edits: z
     .array(
@@ -19,12 +18,22 @@ export const MultiEditTool = Tool.define("multiedit", {
       }),
     )
     .describe("Array of edit operations to perform sequentially on the file"),
-  }),
+})
-  async execute(params, ctx) {
+
-    const tool = await EditTool.init()
+export const MultiEditTool = Tool.defineEffect(
+  "multiedit",
+  Effect.gen(function* () {
+    const tool = yield* Tool.init(EditTool)
+
+    return {
+      description: DESCRIPTION,
+      parameters: Parameters,
+      execute: (params: z.infer<typeof Parameters>, ctx: Tool.Context) =>
+        Effect.gen(function* () {
           const results = []
           for (const [, edit] of params.edits.entries()) {
-      const result = await tool.execute(
+            const result = yield* Effect.promise(() =>
+              tool.execute(
                 {
                   filePath: params.filePath,
                   oldString: edit.oldString,
@@ -32,6 +41,7 @@ export const MultiEditTool = Tool.define("multiedit", {
                   replaceAll: edit.replaceAll,
                 },
                 ctx,
+              ),
             )
             results.push(result)
           }
@@ -42,5 +52,7 @@ export const MultiEditTool = Tool.define("multiedit", {
             },
             output: results.at(-1)!.output,
           }
-  },
+        }).pipe(Effect.orDie, Effect.runPromise),
-})
+    }
+  }),
+)