docs: compare FieldCraft's benchmark results with Abaqus's published values

A README section tabulates, per benchmark, the reference, the result the
Abaqus 2017 Benchmarks Guide publishes (element, mesh, error) and ours from
the oracle, with a cited source per value and notes where the rows are not
like for like. Linked from docs/verification.md.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo

docs/verification.md

@@ -9,6 +9,8 @@ frozen so it cannot drift.
 | Experiment | The model predicts reality | Measurements published in papers and reports (Taylor bar, cavity and cylinder flows, FSI experiments…) |
 | Published benchmarks | Agreement with established codes on standard problems | NAFEMS benchmarks, vendor benchmark and verification manuals (e.g. Abaqus Benchmarks and Verification manuals), other published reference solutions |
 
+How our results compare with the values Abaqus publishes for the same benchmarks: [README, How FieldCraft compares with Abaqus](../README.md#how-fieldcraft-compares-with-abaqus).
+
 Rules:
 - Each case is **our own model** of the problem, built from the published description (geometry,
   material, loads, boundary conditions). We never run a commercial product and never copy its