A position or rotation add/set mutation makes the GSAP timeline the single source of
truth for that channel, so any lingering --hf-studio-offset / --hf-studio-rotation CSS
var must be cleared to avoid double-applying. stripStudioEditsFromTarget now clears both
channels, and the add-strip fires for the position AND rotation property groups.
Also removes the obsolete `gsap_studio_edit_blocked` lint rule: it warned that Studio
cannot save drag/resize edits to elements in a registered timeline — the exact premise
the single-source work inverts (the timeline is now the edit target). Removed the rule,
its now-unused TIMELINE_REGISTRY_ASSIGN_PATTERN import, and its 5 tests.