Plugins: fix env-aware root resolution and caching (#44046)

Merged via squash.

Prepared head SHA: 6e8852a188
Co-authored-by: gumadeiras <5599352+gumadeiras@users.noreply.github.com>
Co-authored-by: gumadeiras <5599352+gumadeiras@users.noreply.github.com>
Reviewed-by: @gumadeiras

src/plugins/providers.test.ts

@@ -0,0 +1,34 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { resolvePluginProviders } from "./providers.js";
+
+const loadOpenClawPluginsMock = vi.fn();
+
+vi.mock("./loader.js", () => ({
+  loadOpenClawPlugins: (...args: unknown[]) => loadOpenClawPluginsMock(...args),
+}));
+
+describe("resolvePluginProviders", () => {
+  beforeEach(() => {
+    loadOpenClawPluginsMock.mockReset();
+    loadOpenClawPluginsMock.mockReturnValue({
+      providers: [{ provider: { id: "demo-provider" } }],
+    });
+  });
+
+  it("forwards an explicit env to plugin loading", () => {
+    const env = { OPENCLAW_HOME: "/srv/openclaw-home" } as NodeJS.ProcessEnv;
+
+    const providers = resolvePluginProviders({
+      workspaceDir: "/workspace/explicit",
+      env,
+    });
+
+    expect(providers).toEqual([{ id: "demo-provider" }]);
+    expect(loadOpenClawPluginsMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        workspaceDir: "/workspace/explicit",
+        env,
+      }),
+    );
+  });
+});