refactor(effect): use SessionRevert service in prompt (#21796)

packages/opencode/test/session/snapshot-tool-race.test.ts

@@ -18,6 +18,7 @@ import path from "path"
 import { Session } from "../../src/session"
 import { LLM } from "../../src/session/llm"
 import { SessionPrompt } from "../../src/session/prompt"
+import { SessionRevert } from "../../src/session/revert"
 import { SessionSummary } from "../../src/session/summary"
 import { MessageV2 } from "../../src/session/message-v2"
 import { Log } from "../../src/util/log"
@@ -143,6 +144,7 @@ function makeHttp() {
   return Layer.mergeAll(
     TestLLMServer.layer,
     SessionPrompt.layer.pipe(
+      Layer.provide(SessionRevert.defaultLayer),
       Layer.provideMerge(run),
       Layer.provideMerge(compact),
       Layer.provideMerge(proc),