Optimize density fitting performance and memory efficiency

[sunqm]

This PR introduces a series of optimizations to the density fitting implementation:

• Optimize density fitting integral computation for general contraction basis sets.
• Improve density fitting Cholesky decomposition cost, reducing initialization time.
• Improve the memory efficiency of loading and decompressing cderi tensor.
• Optimize the density fitting Hessian implementation.
  • reducing memory footprint
  • accelerate derivative integral computation, providing 50%–300% performance improvements.