Add serde support for cxx-qt-lib using proxy types and deriving
#5405
| Job | Run time |
|---|---|
| 13s | |
| 11s | |
| 4s | |
| 11s | |
| 7s | |
| 10m 17s | |
| 1m 46s | |
| 16m 13s | |
| 26m 14s | |
| 24m 50s | |
| 11m 19s | |
| 13m 0s | |
| 17m 39s | |
| 18m 18s | |
| 2h 20m 22s |