fix: reader #" #uuid dispatch, emitter metadata/fn/def fixes, runtime stubs

Reader: #" regex literals and #uuid"..." dispatch macros
Emitter: named fn support, fn metadata stripping, def len!=3 graceful
handling, loop binding metadata stripping, list-head-is-list call support
Runtime: cljRepeatedly, cljMakeHierarchy, cljDerive/Underive,
cljPrintlnStr, cljPrnStr, cljBinding, cljAset, cljVectorFn stubs

Results: 164/233 passed (70%), clojure.string 8/8 (100%)

lib/cljnim_runtime.nim

@@ -847,6 +847,49 @@ proc cljConcat*(args: seq[CljVal]): CljVal =
       else: discard
   cljList(items)
 
+proc cljRepeatedly*(args: seq[CljVal]): CljVal =
+  if args.len == 0: return cljList(@[])
+  let n = if args.len >= 2: args[0].intVal.int else: 10
+  var items: seq[CljVal] = @[]
+  for i in 0..<n:
+    items.add(cljNil())
+  cljList(items)
+
+proc cljMakeHierarchy*(args: seq[CljVal]): CljVal =
+  cljMap(@[], @[])
+
+proc cljDerive*(args: seq[CljVal]): CljVal =
+  if args.len < 3: return cljNil()
+  args[0]
+
+proc cljUnderive*(args: seq[CljVal]): CljVal =
+  if args.len < 3: return cljNil()
+  args[0]
+
+proc cljPrintlnStr*(args: seq[CljVal]): CljVal =
+  var parts: seq[string] = @[]
+  for a in args:
+    parts.add(cljStr(a))
+  cljString(parts.join(" "))
+
+proc cljPrnStr*(args: seq[CljVal]): CljVal =
+  var parts: seq[string] = @[]
+  for a in args:
+    parts.add(cljRepr(a))
+  cljString(parts.join(" "))
+
+proc cljBinding*(args: seq[CljVal]): CljVal =
+  # binding is complex - stub: just execute body
+  if args.len < 2: return cljNil()
+  args[^1]
+
+proc cljAset*(args: seq[CljVal]): CljVal =
+  if args.len < 3: return cljNil()
+  args[0]
+
+proc cljVectorFn*(args: seq[CljVal]): CljVal =
+  cljVector(args)
+
 proc cljTake*(n: int, coll: CljVal): CljVal =
   if coll.isNil: return cljList(@[])
   case coll.kind