Limit recursion to avoid stack overflow (#7657)

Add recursion limit to `def` and `block`.
Summary of this PR , it will detect if `def` call itself or not .
Then execute by using `stack` which I think best choice to use with this
design and core as it is available in all crates and mutable and
calculate the recursion limit on calling `def`.
Set 50 as recursion limit on `Config`.
Add some tests too .

Fixes #5899

Co-authored-by: Reilly Wood <reilly.wood@icloud.com>

crates/nu-engine/src/eval.rs

@@ -876,6 +876,21 @@ pub fn eval_block(
     redirect_stdout: bool,
     redirect_stderr: bool,
 ) -> Result<PipelineData, ShellError> {
+    // if Block contains recursion, make sure we don't recurse too deeply (to avoid stack overflow)
+    if let Some(recursive) = block.recursive {
+        // picked 50 arbitrarily, should work on all architectures
+        const RECURSION_LIMIT: u64 = 50;
+        if recursive {
+            if *stack.recursion_count >= RECURSION_LIMIT {
+                stack.recursion_count = Box::new(0);
+                return Err(ShellError::RecursionLimitReached {
+                    recursion_limit: RECURSION_LIMIT,
+                    span: block.span,
+                });
+            }
+            *stack.recursion_count += 1;
+        }
+    }
     let num_pipelines = block.len();
     for (pipeline_idx, pipeline) in block.pipelines.iter().enumerate() {
         let mut i = 0;