feat(core): add WorkspaceContext (#15409)

packages/opencode/src/control-plane/workspace-context.ts

@@ -0,0 +1,23 @@
+import { Context } from "../util/context"
+
+interface Context {
+  workspaceID?: string
+}
+
+const context = Context.create<Context>("workspace")
+
+export const WorkspaceContext = {
+  async provide<R>(input: { workspaceID?: string; fn: () => R }): Promise<R> {
+    return context.provide({ workspaceID: input.workspaceID }, async () => {
+      return input.fn()
+    })
+  },
+
+  get workspaceID() {
+    try {
+      return context.use().workspaceID
+    } catch (e) {
+      return undefined
+    }
+  },
+}