feat: handle Initial(x) initialization_eqs in time-independent systems
#6331
| Job | Run time |
|---|---|
| 34m 34s | |
| 33s | |
| 16m 15s | |
| 35m 19s | |
| 23m 38s | |
| 14m 17s | |
| 27m 42s | |
| 35m 57s | |
| 38s | |
| 19m 33s | |
| 26m 16s | |
| 21m 8s | |
| 39m 58s | |
| 4h 55m 48s |