feat(mobile): hh launcher + direnv auto-host for Termux/Fairphone

Add a single `hh` launcher (host/join/web/status/stop + operator
passthrough) and a direnv snippet so `cd`-ing into a project dir
auto-hosts a room named after it. Verified live on the Fairphone:
two rooms coexist on port-scoped tmux windows (manual :8799 +
direnv :8801), status health-checks each via curl (ss/netstat are
unreliable on Android), stop-all tears down cleanly.

Termux notes baked in: no /usr/bin/env (invoke via the `hh` alias,
not the shebang); status enumerates operator daemons under
$TMPDIR/hh-bridge.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

scripts/hh-direnv.sh

@@ -0,0 +1,22 @@
+# hh-direnv.sh — source this from a directory's .envrc to auto-host a
+# hack-house room whenever you `cd` in (direnv triggers it).
+#
+#   # .envrc
+#   source "$HOME/hh-mobile/scripts/hh-direnv.sh"
+#
+# The room is named after the directory. Override before sourcing:
+#   export HH_PORT=8801 ; export HH_PASSWORD=hunter2
+#   source "$HOME/hh-mobile/scripts/hh-direnv.sh"
+#
+# Auto-host is ON by default; disable with `export HH_AUTOHOST=0` (env still set).
+
+export HH_NAME="${HH_NAME:-$(basename "$PWD")}"
+export HH_PORT="${HH_PORT:-8799}"
+export HH_PASSWORD="${HH_PASSWORD:-hh-mobile}"
+export HH_BIND="${HH_BIND:-0.0.0.0}"
+
+if [ "${HH_AUTOHOST:-1}" = "1" ]; then
+  # idempotent: the launcher no-ops if the host window already exists
+  bash "$HOME/hh-mobile/scripts/hh" host "$HH_NAME" "$HH_PORT" >/dev/null 2>&1 || true
+  echo "hh: auto-hosting room '$HH_NAME' on :$HH_PORT (HH_AUTOHOST=0 to disable)" >&2
+fi