🐛 point unicity in validity check

[qd-qd]

Issue discovered by @stevieraykatz here

[github-actions]

Changes to gas cost

Generated at commit: 9f9da383f366626a27f19b73754491a93194c27d, compared to commit: 204eec86ef5856ca52a389c9b170cbb8922e02d9

🧾 Summary (20% most significant diffs)

Contract	Method	Avg (+/-)	%
ImplementationCurve	nModInv pModInv	+6 ❌ +7 ❌	+0.03% +0.03%

---

Full diff report 👇

Contract	Deployment Cost (+/-)	Method	Min (+/-)	%	Avg (+/-)	%	Median (+/-)	%	Max (+/-)	%	# Calls (+/-)
ImplementationCurve	146,107 (0)	nModInv pModInv	23,134 (0) 23,112 (0)	0.00% 0.00%	23,275 (+6) 23,235 (+7)	+0.03% +0.03%	23,236 (+42) 23,214 (+42)	+0.18% +0.18%	23,506 (0) 23,484 (0)	0.00% 0.00%	256 (0) 256 (0)

[github-actions]

LCOV of commit 204eec8 during Tests #218

Summary coverage rate:
  lines......: 48.2% (40 of 83 lines)
  functions..: 87.5% (7 of 8 functions)
  branches...: no data found

Files changed coverage rate:
                     |Lines       |Functions  |Branches    
  Filename           |Rate     Num|Rate    Num|Rate     Num
  =========================================================
  src/ECDSA256r1.sol |43.9%     41|66.7%     3|    -      0