Follow the house shell conventions

Constants UPPER_SNAKE, mutable locals PascalCase, braced expansions
throughout, per Development/Coding conventions in the vault.

install/uninstall.sh

@@ -13,11 +13,11 @@ readonly STATE_DIR="${XDG_STATE_HOME:-${HOME}/.local/state}/cd-webhook"
 readonly SYSTEMD_DIR="${HOME}/.config/systemd/user"
 readonly UNIT_NAME="cd-webhook.service"
 
-PURGE=0
-[[ "${1:-}" == "--purge" ]] && PURGE=1
+Purge=0
+[[ "${1:-}" == "--purge" ]] && Purge=1
 
 echo "Stopping ${UNIT_NAME} ..."
-systemctl --user disable --now "$UNIT_NAME" 2>/dev/null || true
+systemctl --user disable --now "${UNIT_NAME}" 2>/dev/null || true
 rm -f "${SYSTEMD_DIR}/${UNIT_NAME}"
 systemctl --user daemon-reload
 
@@ -25,9 +25,9 @@ systemctl --user daemon-reload
 # is regenerated from targets.json plus secrets.env on the next install.
 rm -f "${CONFIG_DIR}/hooks.json"
 
-if [[ $PURGE -eq 1 ]]; then
+if [[ ${Purge} -eq 1 ]]; then
     echo "Purging secrets and deploy logs ..."
-    rm -rf "$CONFIG_DIR" "$STATE_DIR"
+    rm -rf "${CONFIG_DIR}" "${STATE_DIR}"
 else
     echo "Kept ${CONFIG_DIR}/secrets.env and deploy logs in ${STATE_DIR}"
     echo "  (re-run with --purge to remove them too)"