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

packages/opencode/test/session/prompt-effect.test.ts

@@ -25,6 +25,7 @@ import { SessionCompaction } from "../../src/session/compaction"
 import { Instruction } from "../../src/session/instruction"
 import { SessionProcessor } from "../../src/session/processor"
 import { SessionPrompt } from "../../src/session/prompt"
+import { SessionRevert } from "../../src/session/revert"
 import { SessionRunState } from "../../src/session/run-state"
 import { MessageID, PartID, SessionID } from "../../src/session/schema"
 import { SessionStatus } from "../../src/session/status"
@@ -178,6 +179,7 @@ function makeHttp() {
   return Layer.mergeAll(
     TestLLMServer.layer,
     SessionPrompt.layer.pipe(
+      Layer.provide(SessionRevert.defaultLayer),
       Layer.provideMerge(run),
       Layer.provideMerge(compact),
       Layer.provideMerge(proc),