feat(core): add embedded v2 session runtime and tool foundation (#30632)

packages/core/test/opencode.test.ts

@@ -0,0 +1,16 @@
+import { describe, expect } from "bun:test"
+import { Effect } from "effect"
+import { OpenCode } from "@opencode-ai/core/opencode"
+import { testEffect } from "./lib/effect"
+
+const it = testEffect(OpenCode.layer)
+
+describe("OpenCode.layer", () => {
+  it.effect("exposes Sessions through the public embedded API", () =>
+    Effect.gen(function* () {
+      const opencode = yield* OpenCode.Service
+
+      expect(yield* opencode.sessions.list()).toBeArray()
+    }),
+  )
+})