Add "no time signature" / "free composing" option

Your idea

Dear all, I would suggest to implement a "no time signature" / "free composing" function, which might start from the option "Display the note values across the barlines" plus:

• no barlines by default,
• time signatures created automatically, by marking down chords / notes that you want on downbeats,
• no rests in empty measures (there wouldn't be any measure actually)

Problem to be solved

Right now the rhythm grid of musescore is very rigid. You can get around using some tricks, but it would be easier to just have an option for writing more like you would with paper and pencil, so that you don't have to worry already about rhythm if you're just sketching you early ideas.

Prior art

Dorico has some open time signatures options. I'm not aware if it's able to also create time signatures automatically if you mark the desired notes or chords to be on the downbeat.

Additional context

No response

Start by reviewing MuseScore's existing rhythm-grid, measure, barline, and time-signature behavior, then compare the proposed free-composing workflow with the linked Dorico prior art. The issue does not identify files, entry points, or tests, and completion criteria remain broad: define and implement a coherent notation model and user workflow without ordinary measure constraints.