add rendered and json error messages in try/catch (#14082)

# Description

This PR adds a couple more options for dealing with try/catch errors. It
adds a `json` version of the error and a `rendered` version of the
error. It also respects the error_style configuration point.

![image](https://github.com/user-attachments/assets/32574f07-f511-40c0-8b57-de5f6f13a9c4)


# User-Facing Changes
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# Tests + Formatting
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crates/nu-protocol/Cargo.toml

@@ -35,6 +35,7 @@ miette = { workspace = true, features = ["fancy-no-backtrace"] }
 num-format = { workspace = true }
 rmp-serde = { workspace = true, optional = true }
 serde = { workspace = true }
+serde_json = { workspace = true }
 thiserror = "1.0"
 typetag = "0.2"
 os_pipe = { workspace = true, features = ["io_safety"] }

crates/nu-protocol/src/errors/labeled_error.rs

@@ -139,6 +139,23 @@ impl LabeledError {
         self
     }
 
+    pub fn render_error_to_string(diag: impl miette::Diagnostic, fancy_errors: bool) -> String {
+        let theme = if fancy_errors {
+            miette::GraphicalTheme::unicode()
+        } else {
+            miette::GraphicalTheme::none()
+        };
+
+        let mut out = String::new();
+        miette::GraphicalReportHandler::new()
+            .with_width(80)
+            .with_theme(theme)
+            .render_report(&mut out, &diag)
+            .unwrap_or_default();
+
+        out
+    }
+
     /// Create a [`LabeledError`] from a type that implements [`miette::Diagnostic`].
     ///
     /// # Example

crates/nu-protocol/src/errors/shell_error.rs

@@ -1474,13 +1474,16 @@ impl ShellError {
         self.external_exit_code().map(|e| e.item).unwrap_or(1)
     }
 
-    pub fn into_value(self, span: Span) -> Value {
+    pub fn into_value(self, span: Span, fancy_errors: bool) -> Value {
         let exit_code = self.external_exit_code();
 
         let mut record = record! {
             "msg" => Value::string(self.to_string(), span),
             "debug" => Value::string(format!("{self:?}"), span),
-            "raw" => Value::error(self, span),
+            "raw" => Value::error(self.clone(), span),
+            // "labeled_error" => Value::string(LabeledError::from_diagnostic_and_render(self.clone()), span),
+            "rendered" => Value::string(ShellError::render_error_to_string(self.clone(), fancy_errors), span),
+            "json" => Value::string(serde_json::to_string(&self).expect("Could not serialize error"), span),
         };
 
         if let Some(code) = exit_code {
@@ -1499,6 +1502,21 @@ impl ShellError {
             span,
         )
     }
+    pub fn render_error_to_string(diag: impl miette::Diagnostic, fancy_errors: bool) -> String {
+        let theme = if fancy_errors {
+            miette::GraphicalTheme::unicode()
+        } else {
+            miette::GraphicalTheme::none()
+        };
+        let mut out = String::new();
+        miette::GraphicalReportHandler::new()
+            .with_width(80)
+            .with_theme(theme)
+            .render_report(&mut out, &diag)
+            .unwrap_or_default();
+
+        out
+    }
 }
 
 impl From<io::Error> for ShellError {