Hi~ today the trainer went on a little diet!

• The VAE and Text Encoders were freeloaders. Once everything is cached, they just sit on the GPU sunbathing and eating ~2GB of VRAM for no reason. So now we politely walk them over to the CPU couch before training starts, and only invite them back if we actually need them.
• xformers joins the party. The UNet now uses memory-efficient attention when it’s installed, and quietly falls back to plain SDPA if it isn’t — no drama, no crashes.
• The caching progress bar finally tells the truth. Before, it counted already-cached samples as “work” and lied about the ETA. Now we pre-scan everything first, so the bar only moves for real encoding. Honest bar is best bar.
  Result: less VRAM, faster start, happier GPU. Nap successful.

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