handle arbitrary expressions dependent on static input params in proc signatures

tests/generics/tlateboundstatic.nim

@@ -0,0 +1,16 @@
+discard """
+  msg: "array[0..3, int]"
+"""
+
+type
+  KK[I: static[int]] = object
+   x: array[I, int]
+
+proc foo(a: static[string]): KK[a.len] =
+  result.x[0] = 12
+
+var x = foo "test"
+
+import typetraits
+static: echo x.x.type.name
+