P3826 R5 Fix Sender Algorithm Customization

[wg21bot]

P3826R0 Defer Sender Algorithm Customization to C++29 (Eric Niebler)

[inbal2l]

Associated NB comments:

• https://github.com/cplusplus/nbballot/issues/894
• https://github.com/cplusplus/nbballot/issues/903
• https://github.com/cplusplus/nbballot/issues/933
• https://github.com/cplusplus/nbballot/issues/901
• https://github.com/cplusplus/nbballot/issues/906

[wg21bot]

P3826R1 Fix or Remove Sender Algorithm Customization (Eric Niebler)

[wg21bot]

P3826R2 Fix or Remove Sender Algorithm Customization (Eric Niebler)