Merge Luma launcher fork into monorepo

Move trampoline files (boot-hook, watcher, overlay) into trampoline/
subdirectory. Add upstream Luma v2.3.1 source at repo root with our
additions:

- Page::Ha (4th nav tab) with placeholder empty state
- HA tab config schema and default entity mapping (ha-home/)
- Nav keys renamed: "home" → "start", new "ha" tab between Apps and Settings
- All state.rs/view.rs/main.rs/tests.rs updated for 4-tab navigation

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

tv/home.sh

@@ -0,0 +1,51 @@
+#!/bin/sh
+# Optional native Home replacement. The webosbrew hook has no .sh suffix.
+STATE=/var/lib/luma-home
+SCRIPT_DIR=$(CDPATH='' cd -- "$(dirname -- "$0")" && pwd) || exit 1
+COMMAND=${1:-boot}
+case "$COMMAND" in
+  enable|disable|restore|status|apply|boot) ;;
+  *) printf '%s\n' 'Usage: home.sh enable [APP_DIR] | disable | restore | status' >&2; exit 1 ;;
+esac
+[ "$(id -u)" = 0 ] || { printf '%s\n' 'Run as root.' >&2; exit 1; }
+[ -x /usr/bin/node ] || { printf '%s\n' 'The TV Node.js runtime is missing.' >&2; exit 1; }
+if [ "$COMMAND" = enable ]; then
+  printf '%s\n' \
+    'Enabling Luma Home will:' \
+    '  1. Close any running normal Luma instance.' \
+    "  2. Create $STATE with integration scripts, saved state and a staged native Home app linked to Luma." \
+    "  3. Bind-mount $STATE/app over /usr/palm/applications/com.webos.app.home." \
+    '  4. Temporarily block and release Home so SAM rereads its manifest.' \
+    '  5. Stop the previous Home process and launch Luma as Home.' \
+    '  6. Install /var/lib/webosbrew/init.d/64-luma-home to reapply the mount at cold boot.' \
+    '' \
+    "LG Home's original files remain underneath the mount." \
+    'Home Auto Launch and Quick Start+ retain their current settings.' \
+    "Restore LG Home with: sh $STATE/home.sh disable" \
+    ''
+  while :; do
+    printf '%s' 'Apply these changes? [y/n]: '
+    if ! IFS= read -r answer; then
+      printf '\n%s\n' 'Cancelled. No Home integration changes applied.'
+      exit 1
+    fi
+    case "$answer" in
+      y|Y) break ;;
+      n|N) printf '%s\n' 'Cancelled. No Home integration changes applied.'; exit 0 ;;
+      *) printf '%s\n' 'Please answer y or n.' ;;
+    esac
+  done
+fi
+[ ! -L "$STATE" ] || exit 1
+if [ ! -d "$STATE" ]; then mkdir -m 755 "$STATE" || exit 1; fi
+[ "$(stat -c %u "$STATE")" = 0 ] || exit 1
+if [ "$COMMAND" = boot ]; then
+  (
+    sleep 5
+    exec sh "$STATE/home.sh" apply
+  ) </dev/null >>"$STATE/boot.log" 2>&1 &
+  exit 0
+fi
+exec 9>"$STATE/lock"
+flock -n 9 || { printf '%s\n' 'Luma Home integration is already being changed.' >&2; exit 1; }
+exec /usr/bin/node "$SCRIPT_DIR/home.cjs" "$COMMAND" "${2:-$SCRIPT_DIR}"