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-command/src/network/http/client.rs

@@ -1,23 +1,24 @@
 use crate::formats::value_to_json_value;
-use base64::engine::general_purpose::PAD;
-use base64::engine::GeneralPurpose;
-use base64::{alphabet, Engine};
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{EngineState, Stack};
-use nu_protocol::{
-    record, BufferedReader, IntoPipelineData, PipelineData, RawStream, ShellError, Span, Spanned,
-    Value,
+use base64::{
+    alphabet,
+    engine::{general_purpose::PAD, GeneralPurpose},
+    Engine,
+};
+use nu_engine::command_prelude::*;
+use nu_protocol::{BufferedReader, RawStream};
+use std::{
+    collections::HashMap,
+    io::BufReader,
+    path::PathBuf,
+    str::FromStr,
+    sync::{
+        atomic::AtomicBool,
+        mpsc::{self, RecvTimeoutError},
+        Arc,
+    },
+    time::Duration,
 };
 use ureq::{Error, ErrorKind, Request, Response};
-
-use std::collections::HashMap;
-use std::io::BufReader;
-use std::path::PathBuf;
-use std::str::FromStr;
-use std::sync::atomic::AtomicBool;
-use std::sync::mpsc::{self, RecvTimeoutError};
-use std::sync::Arc;
-use std::time::Duration;
 use url::Url;
 
 #[derive(PartialEq, Eq)]

crates/nu-command/src/network/http/delete.rs

@@ -1,17 +1,9 @@
-use nu_engine::CallExt;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Type, Value,
-};
-
 use crate::network::http::client::{
     check_response_redirection, http_client, http_parse_redirect_mode, http_parse_url,
     request_add_authorization_header, request_add_custom_headers, request_handle_response,
-    request_set_timeout, send_request,
+    request_set_timeout, send_request, RequestFlags,
 };
-
-use super::client::RequestFlags;
+use nu_engine::command_prelude::*;
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/http/get.rs

@@ -1,15 +1,9 @@
-use nu_engine::CallExt;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Type, Value,
-};
-
 use crate::network::http::client::{
     check_response_redirection, http_client, http_parse_redirect_mode, http_parse_url,
     request_add_authorization_header, request_add_custom_headers, request_handle_response,
     request_set_timeout, send_request, RequestFlags,
 };
+use nu_engine::command_prelude::*;
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/http/head.rs

@@ -1,18 +1,11 @@
-use std::sync::atomic::AtomicBool;
-use std::sync::Arc;
-
-use nu_engine::CallExt;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Type, Value,
-};
-
 use crate::network::http::client::{
     check_response_redirection, http_client, http_parse_redirect_mode, http_parse_url,
     request_add_authorization_header, request_add_custom_headers, request_handle_response_headers,
     request_set_timeout, send_request,
 };
+use nu_engine::command_prelude::*;
+
+use std::sync::{atomic::AtomicBool, Arc};
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/http/http_.rs

@@ -1,9 +1,4 @@
-use nu_engine::get_full_help;
-use nu_protocol::{
-    ast::Call,
-    engine::{Command, EngineState, Stack},
-    Category, IntoPipelineData, PipelineData, ShellError, Signature, Type, Value,
-};
+use nu_engine::{command_prelude::*, get_full_help};
 
 #[derive(Clone)]
 pub struct Http;

crates/nu-command/src/network/http/options.rs

@@ -1,16 +1,8 @@
-use nu_engine::CallExt;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Type, Value,
-};
-
 use crate::network::http::client::{
     http_client, http_parse_url, request_add_authorization_header, request_add_custom_headers,
-    request_handle_response, request_set_timeout, send_request,
+    request_handle_response, request_set_timeout, send_request, RedirectMode, RequestFlags,
 };
-
-use super::client::{RedirectMode, RequestFlags};
+use nu_engine::command_prelude::*;
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/http/patch.rs

@@ -1,17 +1,9 @@
-use nu_engine::CallExt;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Type, Value,
-};
-
 use crate::network::http::client::{
     check_response_redirection, http_client, http_parse_redirect_mode, http_parse_url,
     request_add_authorization_header, request_add_custom_headers, request_handle_response,
-    request_set_timeout, send_request,
+    request_set_timeout, send_request, RequestFlags,
 };
-
-use super::client::RequestFlags;
+use nu_engine::command_prelude::*;
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/http/post.rs

@@ -1,17 +1,9 @@
-use nu_engine::CallExt;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Type, Value,
-};
-
 use crate::network::http::client::{
     check_response_redirection, http_client, http_parse_redirect_mode, http_parse_url,
     request_add_authorization_header, request_add_custom_headers, request_handle_response,
-    request_set_timeout, send_request,
+    request_set_timeout, send_request, RequestFlags,
 };
-
-use super::client::RequestFlags;
+use nu_engine::command_prelude::*;
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/http/put.rs

@@ -1,17 +1,9 @@
-use nu_engine::CallExt;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Type, Value,
-};
-
 use crate::network::http::client::{
     check_response_redirection, http_client, http_parse_redirect_mode, http_parse_url,
     request_add_authorization_header, request_add_custom_headers, request_handle_response,
-    request_set_timeout, send_request,
+    request_set_timeout, send_request, RequestFlags,
 };
-
-use super::client::RequestFlags;
+use nu_engine::command_prelude::*;
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/port.rs

@@ -1,12 +1,6 @@
-use nu_engine::CallExt;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoPipelineData, Span, Spanned};
-use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4, TcpListener};
+use nu_engine::command_prelude::*;
 
-use nu_protocol::{
-    Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Type, Value,
-};
+use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4, TcpListener};
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/url/build_query.rs

@@ -1,8 +1,4 @@
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, Type, Value,
-};
+use nu_engine::command_prelude::*;
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/url/decode.rs

@@ -1,9 +1,6 @@
 use nu_cmd_base::input_handler::{operate, CellPathOnlyArgs};
-use nu_engine::CallExt;
-use nu_protocol::ast::{Call, CellPath};
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::Category;
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value};
+use nu_engine::command_prelude::*;
+
 use percent_encoding::percent_decode_str;
 
 #[derive(Clone)]

crates/nu-command/src/network/url/encode.rs

@@ -1,10 +1,6 @@
 use nu_cmd_base::input_handler::{operate, CellPathOnlyArgs};
-use nu_engine::CallExt;
-use nu_protocol::ast::Call;
-use nu_protocol::ast::CellPath;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::Category;
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value};
+use nu_engine::command_prelude::*;
+
 use percent_encoding::{utf8_percent_encode, AsciiSet, NON_ALPHANUMERIC};
 
 #[derive(Clone)]

crates/nu-command/src/network/url/join.rs

@@ -1,8 +1,4 @@
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, Type, Value,
-};
+use nu_engine::command_prelude::*;
 
 #[derive(Clone)]
 pub struct SubCommand;

crates/nu-command/src/network/url/mod.rs

@@ -5,8 +5,6 @@ mod join;
 mod parse;
 mod url_;
 
-use url::{self};
-
 pub use self::parse::SubCommand as UrlParse;
 pub use build_query::SubCommand as UrlBuildQuery;
 pub use decode::SubCommand as UrlDecode;

crates/nu-command/src/network/url/parse.rs

@@ -1,10 +1,4 @@
-use super::url;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    record, Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value,
-};
-
+use nu_engine::command_prelude::*;
 use url::Url;
 
 #[derive(Clone)]

crates/nu-command/src/network/url/url_.rs

@@ -1,9 +1,4 @@
-use nu_engine::get_full_help;
-use nu_protocol::{
-    ast::Call,
-    engine::{Command, EngineState, Stack},
-    Category, IntoPipelineData, PipelineData, ShellError, Signature, Type, Value,
-};
+use nu_engine::{command_prelude::*, get_full_help};
 
 #[derive(Clone)]
 pub struct Url;