maude: order-sorted least-sort inference (14 tests, 250 total)

lib/maude/sorts.sx — mau/term-sort computes the least sort of a term (smallest
result sort among op declarations whose arg sorts the actuals satisfy modulo
subsorting); overloaded f(1)=NzNat vs f(s 0)=Nat. mau/has-sort? for
membership-style checks. Answers the plan's order-sorted substrate question.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/maude/scoreboard.json

@@ -1,8 +1,8 @@
 {
   "lang": "maude",
-  "total_passed": 236,
+  "total_passed": 250,
   "total_failed": 0,
-  "total": 236,
+  "total": 250,
   "suites": [
     {"name":"parse","passed":65,"failed":0,"total":65},
     {"name":"reduce","passed":26,"failed":0,"total":26},
@@ -10,6 +10,7 @@
     {"name":"conditional","passed":19,"failed":0,"total":19},
     {"name":"owise","passed":8,"failed":0,"total":8},
     {"name":"gather","passed":7,"failed":0,"total":7},
+    {"name":"sorts","passed":14,"failed":0,"total":14},
     {"name":"rewrite","passed":21,"failed":0,"total":21},
     {"name":"searchpath","passed":8,"failed":0,"total":8},
     {"name":"strategy","passed":19,"failed":0,"total":19},
@@ -17,5 +18,5 @@
     {"name":"pretty","passed":11,"failed":0,"total":11},
     {"name":"run","passed":6,"failed":0,"total":6}
   ],
-  "generated": "2026-06-07T15:43:54+00:00"
+  "generated": "2026-06-07T15:46:14+00:00"
 }