editor.html + pm_e-2.html called _ensureMidi() (requestMIDIAccess{sysex:true}, which always
prompts) on page load. Gate it behind a permission query — only auto-reconnect if MIDI is
already granted (querying does not prompt); otherwise wait for the user to click the connect
badge / Device-audio button. (editor-beta.html already had no on-load MIDI call.)