[Feature request] Create new note in source folder from multiselect; and dynamically update multiselect options from static source with unknown values

## **Is your feature request related to a problem? Please describe.** ### Source: Notes I have a modal form that creates a note for a new appointment or meeting. Several of its fields are multiselect fields that reference folders in my vault; for example, the form asks who the appointment is with, which is a multiselect using my People folder as its Source. When I create an appointmentwith a person who I don't already have a note for in my vault, I have to leave that field blank and remember to go back later, after creating the person note, to fill them in the appointment's metadata. There is no option to "allow unknown values" when the Source for the multiselect field is given as Notes. ### Source: Static Conversely, when the source for the multiselect field is Static, there is an option to allow unknown values, but there is not away toadd those values dynamically to the list of multiselect options when using the form in future. Taking another example, I have a modal form for creating a note about a new medication. One of its fields is a multiselect, from Static source, which asks for timing instructions (when the med should be taken). This includes things like "bedtime", "as needed," "daily," etc. I have "Allow unknown values" checked, so if I get a new medication with a scheduling instruction not already included on my list, e.g. "take with food," I can add it manually in the modal form. But it won't be included in the list of options for future new medications. This means, unless I always remember to edit the form to manually add it later, I gradually accumulate a list of timing instruction values which are not represented on the form, which makes it difficult to standardize data. In the future, I might start another med that needs to be taken with food, and type in "with food", leaving out the word "with", which means those two meds will have different values for that property and will be more difficult to filter for in bases etc. ## **Describe the solution you'd like** ### Source: Notes I'd like something akin to the "allow unknown values" setting that the Static source has, called something like "Allow new note in source folder.". When enabled, I would be able to open the modal form and enter a string into the multiselect field that does not match any existing note and save it as a value entry. When I save the form, a new note would automatically be created in the folder identified as the Source for the multiselect field, with the string I typed as its filename. (This also means that if I have a templates mapped to that folder, it will be applied to the new note.) ### Source: static I would like a toggleable setting called something like "Add new values to list". When enabled, if I type in an unknown value, it would be automatically added to the static list of options and included in future when I open the modal form. **Additional context** <!-- Add any other context or screenshots about the feature request here. -->