Description

Summary of Changes

While working on <>, I was reviewing our SDAM error handling for the first time in a while. Our implementation is slightly from the pseudocode, which made cross referencing them challenging. I refactored the SDAM error handling the best I could:

• All function names now match the spec (i.e., isSDAMUnrecoverableError became isStateChangeError).
• In a similar vein, I've consolidated all "stale error" related logic into a single function to match the spec's implementation.
• I've re-ordered the if-statement in our error handling to be in the same order as the spec's pseudocode.

Someday I'd like to finish this alignment. The largest barrier to fully aligning the implementation with the spec's is that in Node, clearing the pool is done by attaching the ResetPool label to an error and calling markServerUnknown. In the spec algorithm:

markServerUnknown();
clearPool();

This is the last real difference between our implementation and the spec's pseudocode but this refactor would be much more invasive than the refactor in this PR, so I've deferred it for now.

Notes for Reviewers

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