Add an opt-in insecure-TLS mode for the agent, for self-signed certs

Installing the agent against a Homelab Manager instance with a
self-signed cert failed: curl verifies TLS by default on the install
download, the report-tasks.sh fetch inside install.sh, and every
periodic check-in — not just the outer one-liner, so passing -k to only
that first curl wasn't enough. Mirrors the existing Proxmox/Synology
"insecure" toggle pattern already in this app.

- install.sh and report-tasks.sh accept API_INSECURE=true, adding -k to
  their own curl calls; install.sh persists it into the agent's env
  file so the periodic systemd timer picks it up too.
- The Servers & Tasks page has a new checkbox next to the generated
  install/uninstall commands that adds -k and API_INSECURE=true for
  you, so the outer one-liner (which install.sh's own logic can't
  touch) also skips verification.

Off by default — only for a trusted LAN.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

agent/linux/install.sh

@@ -6,16 +6,30 @@
 #   curl -fsSL https://homelab.example.lan/agent/linux/install.sh | \
 #     sudo API_URL=https://homelab.example.lan API_TOKEN=hlm_xxx bash
 #
+# If Homelab Manager is served with a self-signed certificate, also pass
+# API_INSECURE=true (skips TLS verification for every request this agent
+# makes — only do this on a trusted LAN) AND add -k to the outer curl
+# above, since that first fetch of this very script also hits the
+# self-signed endpoint before any of this script's logic can run:
+#   curl -fsSL -k https://homelab.example.lan/agent/linux/install.sh | \
+#     sudo API_URL=https://homelab.example.lan API_TOKEN=hlm_xxx API_INSECURE=true bash
+#
 set -euo pipefail
 
 : "${API_URL:?Set API_URL to your Homelab Manager URL, e.g. https://homelab.example.lan}"
 : "${API_TOKEN:?Set API_TOKEN to the per-server token generated on the Servers & Tasks page}"
+API_INSECURE="${API_INSECURE:-false}"
 
 INSTALL_DIR="/usr/local/bin"
 CONFIG_DIR="/etc"
 SYSTEMD_DIR="/etc/systemd/system"
 INTERVAL_MINUTES="${INTERVAL_MINUTES:-15}"
 
+CURL_INSECURE_FLAG=()
+case "${API_INSECURE,,}" in
+  1|true|yes) CURL_INSECURE_FLAG=(-k) ;;
+esac
+
 if [[ "$EUID" -ne 0 ]]; then
   echo "This installer must be run as root (it installs a systemd timer)." >&2
   echo "If you're piping from curl, put sudo right after the pipe so it elevates bash, not curl:" >&2
@@ -55,13 +69,14 @@ fi
 
 echo "Installing Homelab Manager agent from $API_URL ..."
 
-curl -fsSL "$API_URL/agent/linux/report-tasks.sh" -o "$INSTALL_DIR/homelab-manager-agent.sh"
+curl -fsSL "${CURL_INSECURE_FLAG[@]}" "$API_URL/agent/linux/report-tasks.sh" -o "$INSTALL_DIR/homelab-manager-agent.sh"
 chmod 755 "$INSTALL_DIR/homelab-manager-agent.sh"
 
 umask 077
 cat > "$CONFIG_DIR/homelab-manager-agent.env" <<EOF
 API_URL=$API_URL
 API_TOKEN=$API_TOKEN
+API_INSECURE=$API_INSECURE
 EOF
 chmod 600 "$CONFIG_DIR/homelab-manager-agent.env"
 
@@ -95,4 +110,8 @@ echo "Installed. Running an initial report now..."
 "$INSTALL_DIR/homelab-manager-agent.sh"
 
 echo "Done. The agent reports every ${INTERVAL_MINUTES} minute(s) via the 'homelab-manager-agent.timer' systemd timer."
-echo "To remove it later: curl -fsSL $API_URL/agent/linux/uninstall.sh | sudo bash"
+if [[ ${#CURL_INSECURE_FLAG[@]} -gt 0 ]]; then
+  echo "To remove it later: curl -fsSL -k $API_URL/agent/linux/uninstall.sh | sudo bash"
+else
+  echo "To remove it later: curl -fsSL $API_URL/agent/linux/uninstall.sh | sudo bash"
+fi