Publish a developer-mode Home APK with Home releases (App Studio without a build machine) #510

Since #477 (App Studio on the phone, ADR 0006 milestone 1), a developer Home carries the studio.* tools, and the only way to get one is to build it: rom/scripts/build-home.py --variant standalone --development --dev-mode --package-name dev.makepad.octosense.studio, then adb install beside the store Home. The phone side of the loop needs no computer after that (phone/README.md, "Using App Studio today").

Request: publish that developer-mode Home APK as an asset of each Home release (the standalone-dev-mode build under its test package name), so a developer can download and install it on the phone without a build machine.

What it is and isn't:

• It is a separate package (dev.makepad.octosense.studio) that installs beside the store Home and never replaces it or the Bridge; build-home.py refuses --dev-mode under the installed Home's identity without --development (App Studio on the phone (ADR 0006 milestone 1): #313 rebased, reviewed, re-validated #477, L6 of its review).
• It is not an update: the updater refuses isolated test packages (docs/updater.md), so it stays a download and an install.
• It is not a release of App Studio to non-developers: the studio is compiled only into development builds, developer mode must be turned on in Settings, and the authoring loop runs through the system agent's chat (the full phone authoring experience is ADR 0006's later slices).
• The receipt for such a build records dev_mode and home_package; ROM staging keeps refusing developer-enabled artifacts.

Asked for by the product owner on 12 October 2026, after the question why a computer is still needed to try the studio.