fix(docker): harden /app/extensions permissions to 755 (#30191)

* fix(docker): harden /app/extensions permissions to 755

Bundled extension directories shipped as world-writable (mode 777)
in the Docker image. The plugin security scanner blocks any world-
writable path with:

  WARN: blocked plugin candidate: world-writable path
        (/app/extensions/memory-core, mode=777)

Add chmod -R 755 /app/extensions in the final USER root RUN step so
all bundled extensions are readable but not world-writable. This runs
as root before switching back to the node user, matching the pattern
already used for chmod 755 /app/openclaw.mjs.

Fixes #30139

* fix(docker): normalize plugin and agent path permissions

* docs(changelog): add docker permissions entry for #30191

* Update CHANGELOG.md

---------

Co-authored-by: Vincent Koc <vincentkoc@ieee.org>

src/dockerfile.test.ts

@@ -20,4 +20,11 @@ describe("Dockerfile", () => {
     );
     expect(dockerfile).toContain("apt-get install -y --no-install-recommends xvfb");
   });
+
+  it("normalizes plugin and agent paths permissions in image layers", async () => {
+    const dockerfile = await readFile(dockerfilePath, "utf8");
+    expect(dockerfile).toContain("for dir in /app/extensions /app/.agent /app/.agents");
+    expect(dockerfile).toContain('find "$dir" -type d -exec chmod 755 {} +');
+    expect(dockerfile).toContain('find "$dir" -type f -exec chmod 644 {} +');
+  });
 });