Implement avoidSameFamily geographic criterion

When enabled, avoid pairing players from the same club who have
the same family name (surname). Uses existing player.name field.

api-webapp/src/main/kotlin/org/jeudego/pairgoth/model/Pairing.kt

@@ -87,6 +87,7 @@ data class GeographicalParams(
     val preferMMSDiffRatherThanSameClubsGroup: Int = 2, // Typically = 2
     val preferMMSDiffRatherThanSameClub: Int = 3,       // Typically = 3
     val proportionMainClubThreshold: Double = 0.4, // If the biggest club has a proportion of players higher than this, the secondary criterium is not applied
+    val avoidSameFamily: Boolean = false, // When enabled, avoid pairing players from the same club with the same family name
 ) {
     companion object {
         val disabled = GeographicalParams(avoidSameGeo = 0.0)

api-webapp/src/main/kotlin/org/jeudego/pairgoth/pairing/solver/Solver.kt

@@ -504,7 +504,14 @@ sealed class Solver(
         // else: effectiveCommonClub = true → clubRatio stays 0 (no bonus for same club)
         clubRatio = min(clubRatio, 1.0)
 
-        // TODO Same family
+        // Same family: when enabled and players are from the same club, check if they have the same surname
+        // If so, remove the bonus to avoid pairing family members (even if local club logic gave them a bonus)
+        if (avoidSameFamily && commonClub) {
+            val sameFamily = p1.name.uppercase() == p2.name.uppercase()
+            if (sameFamily) {
+                clubRatio = 0.0  // No bonus for same family within same club
+            }
+        }
 
         // compute geoRatio
         val mainPart = max(countryRatio, clubRatio)