Frametop: a multi-screen desktop and universal 3D mouse for the Steam Frame

Several KDE Plasma screens floating in SteamVR, each a real monitor of any
resolution and shape, shown by our own compositor (ft-screens), with a
layout, wrist pinning, and visibility modes; a Bluetooth mouse that drives
all of SteamVR as a room-anchored 3D pointer (input relay, ft-pointer
helper, ft_pointer SteamVR driver); two settings apps; and Bluetooth LE
fixes. Installs on the headset with ./install.sh.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

AGENTS.md

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+# Working on Frametop
+
+Rules for people and coding agents changing this repo. The README covers what Frametop is and how to install it; `docs/reference.md` covers each component, and `docs/design.md` records how SteamVR on the Frame behaves and why things are built the way they are. Read the findings there before changing how the screens, the pointer, or the input relay talk to SteamVR.
+
+## Two ways to run the scripts
+
+Every script works in both modes, and must keep working in both:
+
+- **On the Frame** (SteamOS, VR variant): commands run locally, in this checkout.
+- **From a PC over SSH:** the repo is synced to `~/dev/frametop` on the Frame (`scripts/sync.sh`), and commands run there. `scripts/_env.sh` works out which mode applies (`FRAME_LOCAL`, `FRAME_HOST`, `FRAME_REPO`).
+
+```
+scripts/sync.sh                          # PC -> ~/dev/frametop on the Frame
+scripts/frame.sh -C <dir> '<build cmd>'  # runs in the "dev" Fedora distrobox
+scripts/frame.sh --host '<cmd>'          # runs on the SteamOS host
+```
+
+- From a PC, edit only on the PC. The Frame's copy is a mirror that `sync.sh` overwrites.
+- Build inside the `dev` container. The SteamOS host has a read-only root and no compilers. Container builds link against the container's libraries, so they run in the container (`distrobox enter dev -- ...`); the SteamVR driver is built to run on the host.
+- Container packages the build needs go in the list in `setup/dev-container.sh`, so the container can be rebuilt.
+- Build output goes in `build/` next to the sources. It's gitignored and never synced.
+
+## The headset may be in use
+
+A Steam Frame is someone's personal headset, and they may be wearing it while you work.
+
+- Don't kill or restart `gamescope`, `steam`, `vrserver`, `vrcompositor`, the gamescope session, or the Frametop desktop without asking. Each one ends or disrupts whatever is happening in VR.
+- Don't run host `sudo`, `steamos-readonly disable`, `steamos-devmode` changes, pacman installs, or reboots without explicit approval. Only the Bluetooth fixes need host `sudo`, and they ask.
+- Write only inside the repo, `/tmp`, and the container unless told otherwise. The installers are the exception: they write the user services, launchers, and the SteamVR driver into the home folder.
+- Never copy `.netrc`, SSH keys, or Steam config off the Frame or into this repo.
+
+## Names
+
+User-facing names are "Frametop", "Frametop Display Settings", and "Frametop Input Settings". Programs and files use the `ft-` / `ft_` prefix (`ft-screens`, `ft-pointer`, `ft-layout`, the `ft_pointer` driver); config, units, and overlay keys use `frametop`. Program names must stay within 15 characters: Linux truncates process names there, and the scripts find programs with `pgrep -x` / `pkill -x`.