Bug 2032055 - feature: add support for connecting to Firefox for Android

[juliandescottes]

This PR adds support for connecting to Firefox for Android via 2 new command line arguments: --android-device and --android-package.

[juliandescottes]

@titooan Here's a PR adding support for Android.

If you can test it with your workflow that would be interesting.
Basically pull the PR, npm run build, then add the following in your claude json, in the section corresponding to your mozilla-central / firefox-main folder.

      "mcpServers": {
        "firefox-devtools": {
          "type": "stdio",
          "command": "./mach",
          "args": [
            "node",
            "/PATH/TO/YOUR/CLONE/dist/index.js", <--- so that you use your locally built mcp
            "--android-device",
            "auto",
            "--android-package",
            "org.mozilla.geckoview_example" <--- I don't know which package you typically use
          ]
        }
      },

[juliandescottes]

I tested both with emulator + geckoviewexample and real device with fenix, and in both cases I could open tabs, navigate, execute script, take screenshots etc... so I think this is ready for review.