Offset metronome beats or set multitrack session's timecode/zero/start point

As far as I know, a multitrack session's timeline always starts at 00:00:00:00 - which is fine for most things. But what if I want the timecode to start at something else? There doesn't seem to be a way to do this. Here's an example where this is a problem:

I have a music track that's 104bpm. I set the metronome so I know where to edit the music track. Unfortunately the music track starts about 1 second from the start of the multitrack session, so the metronome - even though it's set to 104bpm - is out of sync. If I coud set the track's timecode (and therefore the metronome's beat) to start at, say -00:00:01:00, then everything would be in sync.

...Or - a simpler option:

Add an option in the Mutitrack > Metronome... menu to offset the start of the metronome track, so I can simply delay the start of the metronome track by a time that I determine.

...Or, even better:

have a graphical display in the metronome track of the beats and bars that I can either lock, or unlock and drag left/right freely, so set the beats/bars wherever I choose. This would be a fantastic option and I'm sure everyone would be delighted by the ability to match up the metronome with the waveform of a music track.