fix: var hoisting in emitBlock for def inside deftest bodies

- emitBlock now hoists 'var' declarations out of IIFE wrappers
- emitProgramInternal cleaned up (removed debug output)
- Exception type mapping: unknown types preserved (e.g. ValueError)
- 230/233 compliance (98.7%), 78/80 unit tests (97.5%)

src/emitter.nim

@@ -1923,8 +1923,26 @@ proc emitBlock(items: seq[CljVal], indent: int, useResult: bool = false): string
         else:
           code = indentStr(indent) & "discard " & stripped
       else:
-        let indentedCode = indentCode(code, 1)
-        code = indentStr(indent) & "discard ((proc (): CljVal =\n" & indentedCode & "\n" & indentStr(indent) & ")())"
+        # Multi-line code — check if it starts with a var declaration that should be hoisted
+        let codeLines = code.split("\n")
+        let firstLine = codeLines[0].strip()
+        if firstLine.startsWith("var ") and firstLine.contains(" = "):
+          # Split: emit var decl directly at current indent, wrap remaining in IIFE
+          if codeLines.len > 1:
+            var restLines: seq[string] = @[]
+            for li in 1..<codeLines.len:
+              restLines.add(codeLines[li])
+            let rest = restLines.join("\n").strip()
+            if rest.len > 0:
+              let indentedRest = indentCode(restLines.join("\n"), 1)
+              code = indentStr(indent) & firstLine & "\n" & indentStr(indent) & "discard ((proc (): CljVal =\n" & indentedRest & "\n" & indentStr(indent) & ")())"
+            else:
+              code = indentStr(indent) & firstLine
+          else:
+            code = indentStr(indent) & firstLine
+        else:
+          let indentedCode = indentCode(code, 1)
+          code = indentStr(indent) & "discard ((proc (): CljVal =\n" & indentedCode & "\n" & indentStr(indent) & ")())"
     elif useResult:
       if stripped.startsWith("discard "):
         code = indentStr(indent) & "result = " & stripped[8..^1]