feat(silverbullet): add optional Runtime API install via Chromium (#15761)

Adds an install-time prompt to optionally enable Silverbullet's Runtime API by installing Chromium and configuring SB_CHROME_PATH / SB_CHROME_DATA_DIR.

install/silverbullet-install.sh

@@ -16,6 +16,17 @@ update_os
 fetch_and_deploy_gh_release "silverbullet" "silverbulletmd/silverbullet" "prebuild" "latest" "/opt/silverbullet/bin" "silverbullet-server-linux-$(arch_resolve "x86_64" "aarch64").zip"
 mkdir -p /opt/silverbullet/space
 
+RUNTIME_API_ENV=""
+read -rp "${TAB3}Enable Silverbullet Runtime API? Requires Chromium (~700MB). Uses ~200MB extra RAM. (y/N): " runtime_api_prompt
+if [[ "${runtime_api_prompt,,}" =~ ^(y|yes)$ ]]; then
+  msg_info "Installing Chromium for Runtime API"
+  $STD apt install -y chromium
+  msg_ok "Installed Chromium for Runtime API"
+  RUNTIME_API_ENV=$'Environment=SB_CHROME_PATH=/usr/bin/chromium\nEnvironment=SB_CHROME_DATA_DIR=/opt/silverbullet/space/.chrome-data\n'
+  touch /opt/silverbullet/.runtime-api-enabled
+  msg_ok "Runtime API will be enabled"
+fi
+
 msg_info "Creating Service"
 cat <<EOF >/etc/systemd/system/silverbullet.service
 [Unit]
@@ -25,6 +36,7 @@ After=syslog.target network.target
 [Service]
 User=root
 Type=simple
+${RUNTIME_API_ENV}
 ExecStart=/opt/silverbullet/bin/silverbullet --hostname 0.0.0.0 --port 3000 /opt/silverbullet/space
 WorkingDirectory=/opt/silverbullet
 Restart=on-failure