Summary: Tensor.Art adds SRPO support for Flux models

Why It Matters: This change makes images from Flux models look better. It fixes a common problem with AI-generated images.

What Changed:

• A "Sign In" link was added to the top navigation.
• A new article about "TA Update Log" was added.
• The "TA Update Log" article now mentions SRPO support for Flux models.
• The "TA Update Log" article now mentions HunyuanImage 2.1 update.
• Some user-generated content (templates, models, workflows) was updated with new counts or new items.
• Some Japanese text about terms and conditions was removed from the bottom of the page.