fix: relay Signals reset to plugins (#13510)

This PR will close #13501

# Description

This PR expands on [the relay of signals to running plugin
processes](https://github.com/nushell/nushell/pull/13181). The Ctrlc
relay has been generalized to SignalAction::Interrupt and when
reset_signal is called on the main EngineState, a SignalAction::Reset is
now relayed to running plugins.

# User-Facing Changes

The signal handler closure now takes a `signals::SignalAction`, while
previously it took no arguments. The handler will now be called on both
interrupt and reset. The method to register a handler on the plugin side
is now called `register_signal_handler` instead of
`register_ctrlc_handler`
[example](https://github.com/nushell/nushell/pull/13510/files#diff-3e04dff88fd0780a49778a3d1eede092ec729a1264b4ef07ca0d2baa859dad05L38).
This will only affect plugin authors who have started making use of
https://github.com/nushell/nushell/pull/13181, which isn't currently
part of an official release.

The change will also require all of user's plugins to be recompiled in
order that they don't error when a signal is received on the
PluginInterface.

# Testing

```
: example ctrlc
interrupt status: false
waiting for interrupt signal...
^Cinterrupt status: true
peace.
Error:   × Operation interrupted
   ╭─[display_output hook:1:1]
 1 │ if (term size).columns >= 100 { table -e } else { table }
   · ─┬
   ·  ╰── This operation was interrupted
   ╰────

: example ctrlc
interrupt status: false   <-- NOTE status is false
waiting for interrupt signal...
^Cinterrupt status: true
peace.
Error:   × Operation interrupted
   ╭─[display_output hook:1:1]
 1 │ if (term size).columns >= 100 { table -e } else { table }
   · ─┬
   ·  ╰── This operation was interrupted
   ╰────
   ```

crates/nu-plugin-engine/src/interface/mod.rs

@@ -12,7 +12,7 @@ use nu_plugin_protocol::{
 };
 use nu_protocol::{
     ast::Operator, engine::Sequence, CustomValue, IntoSpanned, PipelineData, PluginMetadata,
-    PluginSignature, ShellError, Signals, Span, Spanned, Value,
+    PluginSignature, ShellError, SignalAction, Signals, Span, Spanned, Value,
 };
 use nu_utils::SharedCow;
 use std::{
@@ -664,9 +664,9 @@ impl PluginInterface {
         self.flush()
     }
 
-    /// Send the plugin a ctrl-c signal.
-    pub fn ctrlc(&self) -> Result<(), ShellError> {
-        self.write(PluginInput::Ctrlc)?;
+    /// Send the plugin a signal.
+    pub fn signal(&self, action: SignalAction) -> Result<(), ShellError> {
+        self.write(PluginInput::Signal(action))?;
         self.flush()
     }