The `__NEXT_MAJOR__` value in the RN flags doesn't make sense because:
a) The flags are for the next RN major, since it only impacts the
renderers
b) The flags are off, so they're not currently in the next major, they
need enabled
c) the flag script didn't support it
This PR adds two aliases to the RN file:
- `__TODO_NEXT_RN_MAJOR__`: flags that need enabled before the next RN
major.
- `__NEXT_RN_MAJOR__`: flags that have been enabled since the last RN
major.
These values will need to be manually kept up to date when we cut a RN
version, but once RN switches to the canary build and aligns all the
flags, this entire file can be deleted.
## Script screen
Notably, I added a TODO value and a legend that prints at the end of the
script:
<img width="1078" alt="Screenshot 2024-03-18 at 8 11 27 PM"
src="https://github.com/facebook/react/assets/2440089/14da9066-f77d-437f-8188-830a31a843c5">
