Add string/binary type color to ByteStream (#12897)

# Description

This PR allows byte streams to optionally be colored as being
specifically binary or string data, which guarantees that they'll be
converted to `Binary` or `String` appropriately on `into_value()`,
making them compatible with `Type` guarantees. This makes them
significantly more broadly usable for command input and output.

There is still an `Unknown` type for byte streams coming from external
commands, which uses the same behavior as we previously did where it's a
string if it's UTF-8.

A small number of commands were updated to take advantage of this, just
to prove the point. I will be adding more after this merges.

# User-Facing Changes
- New types in `describe`: `string (stream)`, `binary (stream)`
- These commands now return a stream if their input was a stream:
  - `into binary`
  - `into string`
  - `bytes collect`
  - `str join`
  - `first` (binary)
  - `last` (binary)
  - `take` (binary)
  - `skip` (binary)
- Streams that are explicitly binary colored will print as a streaming
hexdump
  - example:
    ```nushell
    1.. | each { into binary } | bytes collect
    ```

# Tests + Formatting
I've added some tests to cover it at a basic level, and it doesn't break
anything existing, but I do think more would be nice. Some of those will
come when I modify more commands to stream.

# After Submitting
There are a few things I'm not quite satisfied with:

- **String trimming behavior.** We automatically trim newlines from
streams from external commands, but I don't think we should do this with
internal commands. If I call a command that happens to turn my string
into a stream, I don't want the newline to suddenly disappear. I changed
this to specifically do it only on `Child` and `File`, but I don't know
if this is quite right, and maybe we should bring back the old flag for
`trim_end_newline`
- **Known binary always resulting in a hexdump.** It would be nice to
have a `print --raw`, so that we can put binary data on stdout
explicitly if we want to. This PR doesn't change how external commands
work though - they still dump straight to stdout.

Otherwise, here's the normal checklist:

- [ ] release notes
- [ ] docs update for plugin protocol changes (added `type` field)

---------

Co-authored-by: Ian Manske <ian.manske@pm.me>

crates/nu-cmd-lang/src/core_commands/describe.rs

@@ -163,6 +163,8 @@ fn run(
 
     let description = match input {
         PipelineData::ByteStream(stream, ..) => {
+            let type_ = stream.type_().describe();
+
             let description = if options.detailed {
                 let origin = match stream.source() {
                     ByteStreamSource::Read(_) => "unknown",
@@ -172,14 +174,14 @@ fn run(
 
                 Value::record(
                     record! {
-                        "type" => Value::string("byte stream", head),
+                        "type" => Value::string(type_, head),
                         "origin" => Value::string(origin, head),
                         "metadata" => metadata_to_value(metadata, head),
                     },
                     head,
                 )
             } else {
-                Value::string("byte stream", head)
+                Value::string(type_, head)
             };
 
             if !options.no_collect {