pkgbuild: Install auto-update launch shim

Replace the /usr/bin/grok-bot (and sand) plain symlink with a launch
shim that checks the latest Gitea release, pacman -U's a newer
.pkg.tar.zst when available, then execs the real binary under
/opt/Grok Bot/. Skip with GROK_BOT_NO_UPDATE=1; fail soft on
network/API errors. Bump pkgrel for the packaging change.

#2

PKGBUILD

@@ -10,7 +10,7 @@
 pkgname=grok-bot-bin
 pkgver=0.30.0
 _commit=2385d097738b3719cc5ecd9281a107aa106215f1
-pkgrel=1
+pkgrel=2
 pkgdesc="Grok Bot desktop agent (official .deb repackaged)"
 arch=('x86_64')
 url="https://cursor.com/download/bot"
@@ -31,30 +31,30 @@ depends=(
 )
 optdepends=(
   'libappindicator-gtk3: tray icon support'
+  'curl: auto-update check on launch'
 )
 provides=('grok-bot' 'sand')
 conflicts=('grok-bot' 'sand')
 replaces=('sand')
 options=('!strip' '!debug')
-source=("https://downloads.cursor.com/grokbot/stable/${_commit}/linux/x64/grok-bot_${pkgver}_amd64.deb")
+source=(
+  "https://downloads.cursor.com/grokbot/stable/${_commit}/linux/x64/grok-bot_${pkgver}_amd64.deb"
+  "grok-bot-launch.sh"
+)
 noextract=("grok-bot_${pkgver}_amd64.deb")
-sha256sums=('fb888b2204c8a51c71a9f5f9a2913ac10561f3ef6939c1245ecae4e837d4ada2')
+sha256sums=(
+  'fb888b2204c8a51c71a9f5f9a2913ac10561f3ef6939c1245ecae4e837d4ada2'
+  '886c8b55eb44d2f7812be50dcc1571907dc2d7e755171e67e916f497634f09eb'
+)
 
 package() {
   bsdtar -O -xf "$srcdir/grok-bot_${pkgver}_amd64.deb" data.tar.xz \
     | bsdtar -xJf - -C "$pkgdir"
 
-  if [[ -f "$pkgdir/opt/Grok Bot/grok-bot" ]]; then
-    _bin=grok-bot
-  else
-    _bin=sand
-  fi
-
-  install -dm755 "$pkgdir/usr/bin"
-  ln -sf "/opt/Grok Bot/${_bin}" "$pkgdir/usr/bin/${_bin}"
-  if [[ "$_bin" != grok-bot ]]; then
-    ln -sf "/opt/Grok Bot/${_bin}" "$pkgdir/usr/bin/grok-bot"
-  fi
+  # Auto-update launch shim (not a plain symlink into /opt).
+  install -Dm755 "$srcdir/grok-bot-launch.sh" "$pkgdir/usr/bin/grok-bot"
+  # Keep provides(sand) on PATH; both names run the same shim.
+  ln -sf grok-bot "$pkgdir/usr/bin/sand"
 
   # Path contains a space, so Chromium cannot use the SUID sandbox.
   # Arch/CachyOS kernels have user namespaces; keep chrome-sandbox non-setuid.