Update readme and icons

scripts/sign-firefox.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+DIST_DIR="${ROOT_DIR}/dist/signed"
+
+if [[ -z "${AMO_JWT_ISSUER:-}" || -z "${AMO_JWT_SECRET:-}" ]]; then
+  echo "Missing AMO credentials." >&2
+  echo "Set AMO_JWT_ISSUER and AMO_JWT_SECRET before running this script." >&2
+  exit 1
+fi
+
+mkdir -p "${DIST_DIR}"
+
+cd "${ROOT_DIR}"
+
+# Signs as an unlisted add-on (private distribution).
+npx web-ext sign \
+  --source-dir "${ROOT_DIR}" \
+  --artifacts-dir "${DIST_DIR}" \
+  --channel unlisted \
+  --ignore-files "dist/*" "scripts/*" ".git/*" "*.har" "*.log" "*.tmp"
+
+echo "Signed XPI artifacts are in:"
+echo "${DIST_DIR}"