Add match mode to control whether match conditions combine with AND or OR logic

[dsebastien]

It would be useful to have a match_mode: all | any to control whether match conditions combine with AND or OR logic.

Example:

match:
  match_mode: any    # Default: all (current behavior)
  path_glob: "meetings/**/*.md"
  where:
    tags:
      contains: meeting

Some tools recognize notes by tag OR folder (not both). The current AND-only semantics force splitting into separate types or using extensions

Spec section: Match Rules

[callumalpass]

This is a nice idea, @dsebastien . I'll work on this for the next update.