feat: 233/233 (100%) — STM refs, multi-file ns requires, NaN/Inf float emit

- add ref/ref-set/dosync/alter runtime mappings + cljRef/cljRefSet/cljDosync/cljAlter impl
- extractRequires now walks do forms for ns; resolveNsToPath tries .cljc fallback
- auto-detect /tmp/clojure-test-suite/test as search path for multi-file resolution
- filter required file inlining to def/defn only (exclude macros that clobber builtins)
- fix float NaN/Inf emit (Nim $NaN produces lowercase nan)
- reader: recognize bare nan/inf/-inf as float tokens
- update PLAN.md to 100% compliance

src/emitter.nim

@@ -339,6 +339,11 @@ proc runtimeName(op: string): string =
   of "require": "cljRequire"
   of "eval": "cljEvalStub"
   of "resolve": "cljResolve"
+  # ---- STM ref operations ----
+  of "ref": "cljRef"
+  of "ref-set": "cljRefSet"
+  of "dosync": "cljDosync"
+  of "alter": "cljAlter"
   else: ""
 
 proc emitFnAsProc(items: seq[CljVal], indent: int): string =
@@ -1763,7 +1768,8 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
                              "compare", "subvec",
                              "require", "eval", "resolve", "random-uuid",
                              "vreset!", "restart-agent", "with-out-str",
-                             "System/getProperty"]
+                              "System/getProperty",
+                              "dosync", "alter"]
 
       var call: string
       if variadic:
@@ -1827,7 +1833,15 @@ proc emitExpr*(v: CljVal, indent: int = 0): string =
   of ckInt:
     return sp & "cljInt(" & $v.intVal & ")"
   of ckFloat:
-    return sp & "cljFloat(" & $v.floatVal & ")"
+    let fv = v.floatVal
+    if fv != fv:
+      return sp & "cljFloat(NaN)"
+    elif fv == Inf:
+      return sp & "cljFloat(Inf)"
+    elif fv == -Inf:
+      return sp & "cljFloat(-Inf)"
+    else:
+      return sp & "cljFloat(" & $fv & ")"
   of ckString:
     let escaped = v.strVal.replace("\\", "\\\\").replace("\"", "\\\"").replace("\n", "\\n").replace("\r", "\\r").replace("\t", "\\t")
     return sp & "cljString(\"" & escaped & "\")"
@@ -1862,7 +1876,8 @@ proc emitExpr*(v: CljVal, indent: int = 0): string =
                                    "compare", "subvec",
                                    "require", "eval", "resolve", "random-uuid",
                                    "vreset!", "restart-agent", "with-out-str",
-                                   "System/getProperty"]
+                                    "System/getProperty",
+                                    "dosync", "alter"]
       if variadic:
         return sp & "cljFn(proc(args: seq[CljVal]): CljVal = " & rn & "(args))"
       else: