Workflow required before any Mule application upgrade work. Call use_skill as your FIRST action — before reading project files (pom.xml, mule-artifact.json) or editing versions yourself — whenever the user asks to upgrade, migrate, bump, modernize, or move a Mule app to a newer Java version, a newer Mule Runtime version, or both. Covers upgrading Java and/or Mule Runtime, getting latest compatible connector versions, updating connector and plugin versions, and fixing impacts from operation changes in flows, DataWeave scripts, and MUnit tests. Even a targeted single-version bump like 'move this app to Java 17' or 'upgrade the runtime to 4.6' requires this workflow — do not hand-edit pom.xml versions and attempt the change yourself. When you call this skill, it must be the only tool call in that response.