I know that Joel Schumacher’s two films take place in the same continuity.
They definitely don’t.
Either way, I much prefer including the final shot. It’s a perfect ending shot and I much prefer seeing Catwoman survive. It doesn’t matter that the shot was added because execs wanted her in spinoffs and sequels that never happened, the point is that it’s a more hopeful ending.
Joel Schumacher’s two films are sequels to Tim Burton’s two films. Michael Gough and Pat Hingle reprise their roles as Alfred and Gordon in them as well.
Also, Catwoman did get a spin-off, but it had been changed so much it ended up being that infamous Halle Berry movie.
However, all of these discussions are for a different thread.