What do you do if the ball is jammed between the flagstick and the edge of the hole because of the wind and half of it is over the edge of the hole?

There are two possible reasons for this:

1. the ball has already been markedly picked up and put back on the green or
2. the ball has not yet been picked up and put back.

See Rule 13.1d paragraph (2)
When a ball moved by natural forces is to be put back.
If natural forces cause a player's ball to move on the green, the place from which the player must continue play depends on whether the ball has already been picked up and returned to its original position.
the ball has already been picked up and returned to its original position:

Point 1
-Ball already picked up and returned. The ball must be returned to its original position (which, if not known, must be estimated), see Rule 14.2, even though it was moved by natural forces and not by the player, opponent or outside influence (see exception to Rule 9.3).

Point 2
-The ball has not yet been picked up and put back. The ball must be played from its new position (see Rule 9.3).
In this case, but only for point 2, the ball is deemed to have been holed!!!!
See also Rule 13.2c
13.2c Ball rests on the flagstick in the hole
If a player's ball comes to rest on the flagstick in the hole,
-the ball is considered to be holed if it is partially below the surface of the green in the hole, even if the ball is not completely below the surface of the green.
-If the ball is not partially below the surface of the green in the hole, the ball is not holed and must be played as it lies.
If the flagstick is removed and the ball moves (whether it falls into the hole or moves away from the hole), this is not penalised and the ball must be returned to the edge of the hole (see Rule 14.2).

In the meantime, if you would like to know more about the Rules of Golf, please contact me directly at hans.kienesberger@golf.at.