[compiler] Add fault tolerance plan document (#35872)

Add detailed plan for making the React Compiler fault-tolerant by
accumulating errors across all passes instead of stopping at the first
error. This enables reporting multiple compilation errors at once.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/35872).
* #35888
* #35884
* #35883
* #35882
* #35881
* #35880
* #35879
* #35878
* #35877
* #35876
* #35875
* #35874
* #35873
* __->__ #35872