new-style concept bugfix (#24858)

Combining two small PRs in one here. The test case explains what was
wrong with the concepts and for naitivesockets, it's typical to adjust
`ai_flags` so I opened that up.

(cherry picked from commit d4098e6ca0)

compiler/concepts.nim

@@ -347,10 +347,11 @@ proc matchType(c: PContext; fo, ao: PType; m: var MatchCon): bool =
         k1 = f.kidsLen - ord(f.kind == tyGenericInst)
         k2 = ea.kidsLen - ord(ea.kind == tyGenericInst)
       if sameType(f.genericHead, ea.genericHead) and k1 == k2:
+        result = true
         for i in 1 ..< k2:
           if not matchType(c, f[i], ea[i], m):
+            result = false
             break
-        result = true
   of tyOrdinal:
     result = isOrdinalType(a, allowEnumWithHoles = false) or a.kind == tyGenericParam
   of tyStatic:

tests/concepts/tconceptsv2.nim

@@ -459,6 +459,32 @@ block:
   var s = ArrayBuffer[1500]()
   spring(s, 8.uint8)
 
+block:
+  type
+    Future[T] = object
+    SyncType = concept
+      proc p(s: Self)
+    AsyncType = concept
+      proc p(s: Self) : Future[void]
+    SyncImpl = object
+    AsyncImpl = object
+    Container[T] = object
+
+  proc p(x: SyncImpl) = discard
+  proc p(x: AsyncImpl): Future[void] = discard
+
+  proc p(x: Container[SyncType]) = discard
+  proc p(x: Container[AsyncImpl]): Future[void] = discard
+
+  assert SyncImpl is SyncType
+  assert SyncImpl isnot AsyncType
+  assert AsyncImpl isnot SyncType
+  assert AsyncImpl is AsyncType
+  assert Container[SyncImpl] is SyncType
+  assert Container[SyncImpl] isnot AsyncType
+  assert Container[AsyncImpl] isnot SyncType
+  assert Container[AsyncImpl] is AsyncType
+
 # this code fails inside a block for some reason
 type Indexable[T] = concept
   proc `[]`(t: Self, i: int): T