fix(core): load config across git boundaries (#36577)

Co-authored-by: 𝓛𝓲𝓽𝓽𝓵𝓮 𝓕𝓻𝓪𝓷𝓴 <little-frank@opencord.local>
Co-authored-by: opencode-agent[bot] <opencode-agent[bot]@users.noreply.github.com>

packages/opencode/test/config/config.test.ts

@@ -999,37 +999,6 @@ it.instance("resolves scoped npm plugins in config", () =>
   }),
 )
 
-it.effect("loads shared config above a child git repository", () =>
-  Effect.gen(function* () {
-    const root = yield* tmpdirScoped()
-    const global = yield* tmpdirScoped()
-    const workspace = path.join(root, "workspace")
-    const project = path.join(workspace, "project")
-
-    yield* writeConfigEffect(path.join(workspace, ".opencode"), {
-      model: "shared/model",
-      username: "shared-user",
-    })
-    yield* writeConfigEffect(path.join(project, ".opencode"), { username: "project-user" })
-    yield* Effect.promise(async () => {
-      const child = Bun.spawn(["git", "init"], { cwd: project, stdout: "ignore", stderr: "ignore" })
-      await child.exited
-    })
-
-    yield* withGlobalConfigDir(
-      global,
-      withInstanceDir(
-        project,
-        Effect.gen(function* () {
-          const config = yield* Config.use.get()
-          expect(config.model).toBe("shared/model")
-          expect(config.username).toBe("project-user")
-        }),
-      ),
-    )
-  }),
-)
-
 it.effect("merges plugin arrays from global and local configs", () =>
   withConfigTree(
     {