feat(core): add scout agent for repo research (#24149)

Co-authored-by: Dax Raad <d@ironbay.co>

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

@@ -30,6 +30,7 @@ import { TestLLMServer } from "../lib/llm-server"
 // Same layer setup as prompt-effect.test.ts
 import { NodeFileSystem } from "@effect/platform-node"
 import { Agent as AgentSvc } from "../../src/agent/agent"
+import { Git } from "../../src/git"
 import { Bus } from "../../src/bus"
 import { Command } from "../../src/command"
 import { Config } from "@/config/config"
@@ -128,6 +129,7 @@ function makeHttp() {
     Layer.provide(Skill.defaultLayer),
     Layer.provide(FetchHttpClient.layer),
     Layer.provide(CrossSpawnSpawner.defaultLayer),
+    Layer.provide(Git.defaultLayer),
     Layer.provide(Ripgrep.defaultLayer),
     Layer.provide(Format.defaultLayer),
     Layer.provideMerge(todo),