Add command_prelude module (#12291)

# Description
When implementing a `Command`, one must also import all the types
present in the function signatures for `Command`. This makes it so that
we often import the same set of types in each command implementation
file. E.g., something like this:
```rust
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData,
    ShellError, Signature, Span, Type, Value,
};
```

This PR adds the `nu_engine::command_prelude` module which contains the
necessary and commonly used types to implement a `Command`:
```rust
// command_prelude.rs
pub use crate::CallExt;
pub use nu_protocol::{
    ast::{Call, CellPath},
    engine::{Command, EngineState, Stack},
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, IntoSpanned,
    PipelineData, Record, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
};
```

This should reduce the boilerplate needed to implement a command and
also gives us a place to track the breadth of the `Command` API. I tried
to be conservative with what went into the prelude modules, since it
might be hard/annoying to remove items from the prelude in the future.
Let me know if something should be included or excluded.

crates/nu-cli/src/repl.rs

@@ -9,8 +9,10 @@ use crate::{
 use crossterm::cursor::SetCursorStyle;
 use log::{error, trace, warn};
 use miette::{ErrReport, IntoDiagnostic, Result};
-use nu_cmd_base::util::get_guaranteed_cwd;
-use nu_cmd_base::{hook::eval_hook, util::get_editor};
+use nu_cmd_base::{
+    hook::eval_hook,
+    util::{get_editor, get_guaranteed_cwd},
+};
 use nu_color_config::StyleComputer;
 use nu_engine::{convert_env_values, env_to_strings};
 use nu_parser::{lex, parse, trim_quotes_str};
@@ -31,8 +33,7 @@ use std::{
     env::temp_dir,
     io::{self, IsTerminal, Write},
     panic::{catch_unwind, AssertUnwindSafe},
-    path::Path,
-    path::PathBuf,
+    path::{Path, PathBuf},
     sync::{atomic::Ordering, Arc},
     time::{Duration, Instant},
 };