feat(ovsm): Add sleep function and fix tight loop issue

Problem: WebSocket streaming script hit 10M iteration limit
- Tight while loop without delay
- stream-poll returns instantly when buffer empty
- Loop spins millions of times per second

Solution: Add sleep(milliseconds) function
- Pauses execution for specified milliseconds
- Uses std::thread::sleep internally
- Update stream script to sleep 100ms between polls

Script changes:
- Restore 60 second duration (was reduced to 10)
- Add sleep(100) in poll loop
- Add poll-count stat to show polling frequency
- Now ~600 polls in 60 seconds (1 every 100ms)

Benefits:
- No more iteration limit errors
- CPU friendly (no busy-wait spinning)
- Still responsive (100ms latency acceptable)
- WebSocket events buffered while sleeping

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: 0xrinegade

crates/ovsm/src/runtime/lisp_evaluator.rs

@@ -320,6 +320,7 @@ impl LispEvaluator {
                     "clamp" => self.eval_clamp(args), // Clamp between min/max
                     "random" => self.eval_random(args), // Random number
                     "now" => self.eval_now(args),
+                    "sleep" => self.eval_sleep(args),
                     "log" => self.eval_log(args),
                     "print" => self.eval_print(args), // Python/JS-style output
                     "println" => self.eval_println(args), // Python/JS-style output with newline
@@ -4016,6 +4017,31 @@ impl LispEvaluator {
         Ok(Value::Int(timestamp as i64))
     }
 
+    /// (sleep milliseconds) - Sleep for specified milliseconds
+    fn eval_sleep(&mut self, args: &[crate::parser::Argument]) -> Result<Value> {
+        if args.len() != 1 {
+            return Err(Error::InvalidArguments {
+                tool: "sleep".to_string(),
+                reason: format!("Expected 1 argument, got {}", args.len()),
+            });
+        }
+
+        let val = self.evaluate_expression(&args[0].value)?;
+        let ms = match val {
+            Value::Int(i) => i as u64,
+            Value::Float(f) => f as u64,
+            _ => {
+                return Err(Error::TypeError {
+                    expected: "number".to_string(),
+                    got: val.type_name().to_string(),
+                })
+            }
+        };
+
+        std::thread::sleep(std::time::Duration::from_millis(ms));
+        Ok(Value::Null)
+    }
+
     /// (base58-encode string) - Encode string to base58
     fn eval_base58_encode(&mut self, args: &[crate::parser::Argument]) -> Result<Value> {
         if args.len() != 1 {

examples/ovsm_scripts/stream_pumpfun.ovsm

@@ -27,12 +27,17 @@
 (define graduation-count 0)
 (define transfer-count 0)
 
-;; Main event loop (60 seconds)
+;; Main event loop (60 seconds with sleep to avoid spinning CPU)
 (define start-time (now))
 (define duration 60)
+(define poll-count 0)
 
 (while (< (- (now) start-time) duration)
   (define events (stream-poll stream-id :limit 50))
+  (set! poll-count (+ poll-count 1))
+
+  ;; Sleep 100ms between polls to avoid tight loop
+  (sleep 100)
 
   (for (event events)
     (define event-type (get event "type"))
@@ -128,6 +133,7 @@
 (println "  FORENSICS SUMMARY")
 (println "═══════════════════════════════════════════════════════════════")
 (println (str "Duration:         " duration " seconds"))
+(println (str "Poll Count:       " poll-count " polls"))
 (println (str "Buy Txs:          " buy-count))
 (println (str "Sell Txs:         " sell-count))
 (println (str "Token Transfers:  " transfer-count))