fix: expand variadic list + add runtime stubs — 174/233 (74%)

Runtime: cljCompare, cljSubvec, cljRand, cljRandInt, cljRandNth,
cljRandomSample with native Nim implementations
Emitter: expanded variadic function list for correct seq[CljVal] calling

Results: 174/233 passed (74%)
  clojure.string: 8/8 (100%)
  clojure.core: 166/225 (74%)

lib/cljnim_runtime.nim

@@ -1,6 +1,6 @@
 import cljnim_pvec
 import cljnim_pmap
-import strutils, sequtils, hashes, algorithm, os, osproc, locks, math
+import strutils, sequtils, hashes, algorithm, os, osproc, locks, math, random
 
 type
   CljKind* = enum
@@ -890,6 +890,95 @@ proc cljAset*(args: seq[CljVal]): CljVal =
 proc cljVectorFn*(args: seq[CljVal]): CljVal =
   cljVector(args)
 
+proc cljCompare*(args: seq[CljVal]): CljVal =
+  if args.len < 2: return cljInt(0)
+  let a = args[0]; let b = args[1]
+  if a.isNil and b.isNil: return cljInt(0)
+  if a.isNil: return cljInt(-1)
+  if b.isNil: return cljInt(1)
+  case a.kind
+  of ckInt:
+    if b.kind == ckInt:
+      if a.intVal < b.intVal: return cljInt(-1)
+      elif a.intVal > b.intVal: return cljInt(1)
+      else: return cljInt(0)
+    elif b.kind == ckFloat:
+      if a.intVal.float < b.floatVal: return cljInt(-1)
+      elif a.intVal.float > b.floatVal: return cljInt(1)
+      else: return cljInt(0)
+  of ckFloat:
+    if b.kind == ckFloat:
+      if a.floatVal < b.floatVal: return cljInt(-1)
+      elif a.floatVal > b.floatVal: return cljInt(1)
+      else: return cljInt(0)
+    elif b.kind == ckInt:
+      if a.floatVal < b.intVal.float: return cljInt(-1)
+      elif a.floatVal > b.intVal.float: return cljInt(1)
+      else: return cljInt(0)
+  of ckString:
+    if b.kind == ckString:
+      if a.strVal < b.strVal: return cljInt(-1)
+      elif a.strVal > b.strVal: return cljInt(1)
+      else: return cljInt(0)
+  of ckKeyword:
+    if b.kind == ckKeyword:
+      if a.kwName < b.kwName: return cljInt(-1)
+      elif a.kwName > b.kwName: return cljInt(1)
+      else: return cljInt(0)
+  else: discard
+  cljInt(0)
+
+proc cljSubvec*(args: seq[CljVal]): CljVal =
+  if args.len < 2: return cljVector(@[])
+  let v = args[0]
+  let start = args[1].intVal.int
+  let stop = if args.len >= 3: args[2].intVal.int else: (if v.kind == ckVector: v.vecData.count else: 0)
+  if v.kind != ckVector: return cljVector(@[])
+  var items: seq[CljVal] = @[]
+  for i in start..<min(stop, v.vecData.count):
+    items.add(v.vecData[i])
+  cljVector(items)
+
+proc cljRand*(args: seq[CljVal]): CljVal =
+  if args.len == 0: return cljFloat(rand(1.0))
+  let n = args[0]
+  case n.kind
+  of ckInt: return cljInt(rand(n.intVal.int).int64)
+  of ckFloat: return cljFloat(rand(n.floatVal))
+  else: return cljFloat(rand(1.0))
+
+proc cljRandInt*(args: seq[CljVal]): CljVal =
+  if args.len == 0: return cljInt(0)
+  let n = args[0].intVal.int
+  if n <= 0: return cljInt(0)
+  cljInt(rand(n).int64)
+
+proc cljRandNth*(args: seq[CljVal]): CljVal =
+  if args.len == 0: return cljNil()
+  let coll = args[0]
+  case coll.kind
+  of ckVector:
+    if coll.vecData.count == 0: return cljNil()
+    return coll.vecData[rand(coll.vecData.count)]
+  of ckList:
+    let items = coll.listItems
+    if items.len == 0: return cljNil()
+    return items[rand(items.len)]
+  else: return cljNil()
+
+proc cljRandomSample*(args: seq[CljVal]): CljVal =
+  if args.len < 2: return cljList(@[])
+  let coll = args[1]
+  var items: seq[CljVal] = @[]
+  let collItems = case coll.kind
+  of ckList: coll.listItems
+  of ckVector: toSeq(coll.vecData)
+  else: @[]
+  for item in collItems:
+    if rand(1.0) < 0.5:
+      items.add(item)
+  cljList(items)
+
 proc cljTake*(n: int, coll: CljVal): CljVal =
   if coll.isNil: return cljList(@[])
   case coll.kind