Add and use new Signals struct (#13314)

# Description
This PR introduces a new `Signals` struct to replace our adhoc passing
around of `ctrlc: Option<Arc<AtomicBool>>`. Doing so has a few benefits:
- We can better enforce when/where resetting or triggering an interrupt
is allowed.
- Consolidates `nu_utils::ctrl_c::was_pressed` and other ad-hoc
re-implementations into a single place: `Signals::check`.
- This allows us to add other types of signals later if we want. E.g.,
exiting or suspension.
- Similarly, we can more easily change the underlying implementation if
we need to in the future.
- Places that used to have a `ctrlc` of `None` now use
`Signals::empty()`, so we can double check these usages for correctness
in the future.

crates/nu-command/src/conversions/fill.rs

@@ -165,7 +165,7 @@ fn fill(
         cell_paths,
     };
 
-    operate(action, arg, input, call.head, engine_state.ctrlc.clone())
+    operate(action, arg, input, call.head, engine_state.signals())
 }
 
 fn action(input: &Value, args: &Arguments, span: Span) -> Value {

crates/nu-command/src/conversions/into/binary.rs

@@ -138,7 +138,7 @@ fn into_binary(
             cell_paths,
             compact: call.has_flag(engine_state, stack, "compact")?,
         };
-        operate(action, args, input, head, engine_state.ctrlc.clone())
+        operate(action, args, input, head, engine_state.signals())
     }
 }
 

crates/nu-command/src/conversions/into/bool.rs

@@ -107,7 +107,7 @@ fn into_bool(
 ) -> Result<PipelineData, ShellError> {
     let cell_paths: Vec<CellPath> = call.rest(engine_state, stack, 0)?;
     let args = CellPathOnlyArgs::from(cell_paths);
-    operate(action, args, input, call.head, engine_state.ctrlc.clone())
+    operate(action, args, input, call.head, engine_state.signals())
 }
 
 fn string_to_boolean(s: &str, span: Span) -> Result<bool, ShellError> {

crates/nu-command/src/conversions/into/datetime.rs

@@ -141,7 +141,7 @@ impl Command for SubCommand {
                 zone_options,
                 cell_paths,
             };
-            operate(action, args, input, call.head, engine_state.ctrlc.clone())
+            operate(action, args, input, call.head, engine_state.signals())
         }
     }
 

crates/nu-command/src/conversions/into/duration.rs

@@ -166,7 +166,7 @@ fn into_duration(
                 ret
             }
         },
-        engine_state.ctrlc.clone(),
+        engine_state.signals(),
     )
 }
 

crates/nu-command/src/conversions/into/filesize.rs

@@ -68,7 +68,7 @@ impl Command for SubCommand {
     ) -> Result<PipelineData, ShellError> {
         let cell_paths: Vec<CellPath> = call.rest(engine_state, stack, 0)?;
         let args = CellPathOnlyArgs::from(cell_paths);
-        operate(action, args, input, call.head, engine_state.ctrlc.clone())
+        operate(action, args, input, call.head, engine_state.signals())
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/conversions/into/float.rs

@@ -49,7 +49,7 @@ impl Command for SubCommand {
     ) -> Result<PipelineData, ShellError> {
         let cell_paths: Vec<CellPath> = call.rest(engine_state, stack, 0)?;
         let args = CellPathOnlyArgs::from(cell_paths);
-        operate(action, args, input, call.head, engine_state.ctrlc.clone())
+        operate(action, args, input, call.head, engine_state.signals())
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/conversions/into/glob.rs

@@ -87,7 +87,7 @@ fn glob_helper(
         Ok(Value::glob(stream.into_string()?, false, head).into_pipeline_data())
     } else {
         let args = Arguments { cell_paths };
-        operate(action, args, input, head, engine_state.ctrlc.clone())
+        operate(action, args, input, head, engine_state.signals())
     }
 }
 

crates/nu-command/src/conversions/into/int.rs

@@ -158,7 +158,7 @@ impl Command for SubCommand {
             signed,
             cell_paths,
         };
-        operate(action, args, input, call.head, engine_state.ctrlc.clone())
+        operate(action, args, input, call.head, engine_state.signals())
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/conversions/into/record.rs

@@ -125,7 +125,7 @@ fn into_record(
             ),
         },
         Value::Range { val, .. } => Value::record(
-            val.into_range_iter(span, engine_state.ctrlc.clone())
+            val.into_range_iter(span, engine_state.signals().clone())
                 .enumerate()
                 .map(|(idx, val)| (format!("{idx}"), val))
                 .collect(),

crates/nu-command/src/conversions/into/string.rs

@@ -180,7 +180,7 @@ fn string_helper(
             cell_paths,
             config,
         };
-        operate(action, args, input, head, engine_state.ctrlc.clone())
+        operate(action, args, input, head, engine_state.signals())
     }
 }
 

crates/nu-command/src/conversions/into/value.rs

@@ -57,14 +57,12 @@ impl Command for IntoValue {
         call: &Call,
         input: PipelineData,
     ) -> Result<PipelineData, ShellError> {
-        let engine_state = engine_state.clone();
         let metadata = input.metadata();
-        let ctrlc = engine_state.ctrlc.clone();
         let span = call.head;
-        let display_as_filesizes = call.has_flag(&engine_state, stack, "prefer-filesizes")?;
+        let display_as_filesizes = call.has_flag(engine_state, stack, "prefer-filesizes")?;
 
         // the columns to update
-        let columns: Option<Value> = call.get_flag(&engine_state, stack, "columns")?;
+        let columns: Option<Value> = call.get_flag(engine_state, stack, "columns")?;
         let columns: Option<HashSet<String>> = match columns {
             Some(val) => Some(
                 val.into_list()?
@@ -81,7 +79,7 @@ impl Command for IntoValue {
             display_as_filesizes,
             span,
         }
-        .into_pipeline_data(span, ctrlc)
+        .into_pipeline_data(span, engine_state.signals().clone())
         .set_metadata(metadata))
     }
 }