perf(number-field): complete core Phase-4 evidence (#9885)

* perf(number-field): complete Phase 4 evidence

* docs(number-field): reconcile Phase 4 review

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Co-authored-by: Kim Morrison <kim@lean-fro.org>

Author: kim-em

libraries.yml

@@ -1016,7 +1016,7 @@ libraries:
   HexNumberField:
     deps: [HexPolyZ, HexRoots, HexResultant, HexBerlekampZassenhaus, HexMatrix, HexRowReduce]
     mathlib: false
-    done_through: 3
+    done_through: 4
     status: active
     phase4:
       comparators: