v1.8.0

Features

• add Brent root finder (04a3087)
• add Hager-Zhang line search (ddcc6c8)
• add global-best particle swarm optimizer (95dd75d)
• checkpoint: resume stochastic solvers (cc91fc9)
• executor: add exact checkpoints (bd27839)
• solvers: add simulated annealing (231121c)
• executor: add cancellation tokens (7ea852e)
• support versioned linear algebra backends (b26e5e8)
• export TRF damping traits (d4b2ca7), refs #84