chore(INFRA-3037): improve docs

Author: jluque0101

.github/scripts/create-platform-release-pr.sh

@@ -17,6 +17,12 @@
 #   new_version_number      - Build version for mobile platform (optional, required for mobile)
 #   git_user_name           - Git user name for commits (optional, defaults to 'metamaskbot')
 #   git_user_email          - Git user email for commits (optional, defaults to 'metamaskbot@users.noreply.github.com')
+#
+# Environment (optional):
+#   BASE_BRANCH          - The base branch for the release PR (defaults to 'main')
+#   GITHUB_TOKEN         - Token for GitHub CLI operations (falls back to gh auth config)
+#   TEST_ONLY            - When set to "true", uses test branch prefixes and skips changelog PR
+#   GITHUB_REPOSITORY_URL - Full HTTPS URL for the repository (used for changelog generation)
 
 set -e
 set -u