add --raw-value option to debug command (#15581)

# Description

This adds a new option `--raw-value`/`-v` to the `debug` command to
allow you to only get the debug string part of the nushell value.
Because, sometimes you don't need the span or nushell datatype and you
just want the val part.

You can see the difference between `debug -r` and `debug -v` here.

![image](https://github.com/user-attachments/assets/ac16cdf0-2ec8-4f61-a2c4-81341f8d363b)

It should work on all datatypes except Value::Error and Value::Closure.

# User-Facing Changes
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helps us keep track of breaking changes. -->

# Tests + Formatting
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- `cargo fmt --all -- --check` to check standard code formatting (`cargo
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- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used` to
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- `cargo test --workspace` to check that all tests pass (on Windows make
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- `cargo run -- -c "use toolkit.nu; toolkit test stdlib"` to run the
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> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
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# After Submitting
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crates/nu-command/src/debug/debug_.rs

@@ -23,6 +23,11 @@ impl Command for Debug {
             ])
             .category(Category::Debug)
             .switch("raw", "Prints the raw value representation", Some('r'))
+            .switch(
+                "raw-value",
+                "Prints the raw value representation but not the nushell value part",
+                Some('v'),
+            )
     }
 
     fn run(
@@ -35,6 +40,7 @@ impl Command for Debug {
         let head = call.head;
         let config = stack.get_config(engine_state);
         let raw = call.has_flag(engine_state, stack, "raw")?;
+        let raw_value = call.has_flag(engine_state, stack, "raw-value")?;
 
         // Should PipelineData::Empty result in an error here?
 
@@ -42,6 +48,11 @@ impl Command for Debug {
             move |x| {
                 if raw {
                     Value::string(x.to_debug_string(), head)
+                } else if raw_value {
+                    match x.coerce_into_string_all() {
+                        Ok(s) => Value::string(format!("{s:#?}"), head),
+                        Err(e) => Value::error(e, head),
+                    }
                 } else {
                     Value::string(x.to_expanded_string(", ", &config), head)
                 }
@@ -78,10 +89,75 @@ impl Command for Debug {
                     Span::test_data(),
                 )),
             },
+            Example {
+                description: "Debug print an ansi escape encoded string and get the raw value",
+                example: "$'(ansi red)nushell(ansi reset)' | debug -v",
+                result: Some(Value::test_string("\"\\u{1b}[31mnushell\\u{1b}[0m\"")),
+            },
         ]
     }
 }
 
+// This is just a local Value Extension trait to avoid having to
+// put another *_to_string() converter in nu_protocol
+trait ValueExt {
+    fn coerce_into_string_all(&self) -> Result<String, ShellError>;
+    fn cant_convert_to<T>(&self, typ: &str) -> Result<T, ShellError>;
+}
+
+impl ValueExt for Value {
+    fn cant_convert_to<T>(&self, typ: &str) -> Result<T, ShellError> {
+        Err(ShellError::CantConvert {
+            to_type: typ.into(),
+            from_type: self.get_type().to_string(),
+            span: self.span(),
+            help: None,
+        })
+    }
+
+    fn coerce_into_string_all(&self) -> Result<String, ShellError> {
+        let span = self.span();
+        match self {
+            Value::Bool { val, .. } => Ok(val.to_string()),
+            Value::Int { val, .. } => Ok(val.to_string()),
+            Value::Float { val, .. } => Ok(val.to_string()),
+            Value::String { val, .. } => Ok(val.to_string()),
+            Value::Glob { val, .. } => Ok(val.to_string()),
+            Value::Filesize { val, .. } => Ok(val.get().to_string()),
+            Value::Duration { val, .. } => Ok(val.to_string()),
+            Value::Date { val, .. } => Ok(val.to_rfc3339_opts(chrono::SecondsFormat::Nanos, true)),
+            Value::Range { val, .. } => Ok(val.to_string()),
+            Value::Record { val, .. } => Ok(format!(
+                "{{{}}}",
+                val.iter()
+                    .map(|(x, y)| match y.coerce_into_string_all() {
+                        Ok(value) => format!("{x}: {value}"),
+                        Err(err) => format!("Error: {err}"),
+                    })
+                    .collect::<Vec<_>>()
+                    .join(", ")
+            )),
+            Value::List { vals, .. } => Ok(format!(
+                "[{}]",
+                vals.iter()
+                    .map(|x| match x.coerce_into_string_all() {
+                        Ok(value) => value,
+                        Err(err) => format!("Error: {err}"),
+                    })
+                    .collect::<Vec<_>>()
+                    .join(", ")
+            )),
+            Value::Binary { val, .. } => match String::from_utf8(val.to_vec()) {
+                Ok(s) => Ok(s),
+                Err(err) => Value::binary(err.into_bytes(), span).cant_convert_to("string"),
+            },
+            Value::CellPath { val, .. } => Ok(val.to_string()),
+            Value::Nothing { .. } => Ok("nothing".to_string()),
+            val => val.cant_convert_to("string"),
+        }
+    }
+}
+
 #[cfg(test)]
 mod test {
     #[test]