Cleans up feature flags that do not have an active experiment and which
we don't currently plan to ship, one commit per flag. Notable removals:
* Automatic (inferred) effect dependencies / Fire: abandoned due to
early feedback. Shipped useEffectEvent which addresses some of the
use-cases.
* Inline JSX transform (experimented, not a consistent win)
* Context selectors (experimented, not a sufficient/consistent win given
the benefit the compiler already provides)
* Instruction Reordering (will try a different approach)
To decide which features to remove, I looked at Meta's internal repos as
well as eslint-pugin-react-hooks to see which flags were never
overridden anywhere. That gave a longer list of flags, from which I then
removed some features that I know are used in OSS.
Autogenerated summaries of each of the compiler passes which allow
agents to get the key ideas of a compiler pass, including key
input/output invariants, without having to reprocess the file each time.
In the subsequent diff this seemed to help.
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[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/35595).
* #35607
* #35298
* #35596
* #35573
* __->__ #35595
* #35539
