what finally worked for overriding composer save

i needed to change how composer save behaved without patching core in a brittle way.

after trying a few older patterns, i moved the logic into a plugin that extends the composer model behavior directly and kept the change narrow. the key part was avoiding a broad monkey patch and only touching the save path I actually needed. that kept the change stable across reloads and made it easier to test.

i also verified the flow in local dev with the exact composer action i cared about, because the edge case only showed up when the draft already existed. once i handled that branch, the issue went away and i did not need any extra client-side code.