Enforce required, optional, and rest positional arguments start with an uppercase and end with a period. (#11285)

# Description

This updates all the positional arguments (except with
`--features=dataframe` or `--features=extra`) to start with an uppercase
letter and end with a period.

Part of #5066, specifically [this
comment](/nushell/nushell/issues/5066#issuecomment-1421528910)

Some arguments had example data removed from them because it also
appears in the examples.

There are other inconsistencies in positional arguments I noticed while
making the tests pass which I will bring up in #5066.

# User-Facing Changes

Positional arguments are now consistent

# Tests + Formatting

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting

Automatic documentation updates

crates/nu-command/src/platform/ansi/ansi_.rs

@@ -514,7 +514,7 @@ impl Command for AnsiCommand {
             .optional(
                 "code",
                 SyntaxShape::Any,
-                "the name of the code to use like 'green' or 'reset' to reset the color",
+                "The name of the code to use (from `ansi -l`).",
             )
             .switch(
                 "escape", // \x1b[

crates/nu-command/src/platform/ansi/link.rs

@@ -37,7 +37,7 @@ impl Command for SubCommand {
             .rest(
                 "cell path",
                 SyntaxShape::CellPath,
-                "for a data structure input, add links to all strings at the given cell paths",
+                "For a data structure input, add links to all strings at the given cell paths.",
             )
             .allow_variants_without_examples(true)
             .category(Category::Platform)

crates/nu-command/src/platform/ansi/strip.rs

@@ -24,7 +24,7 @@ impl Command for SubCommand {
             .rest(
                 "cell path",
                 SyntaxShape::CellPath,
-                "for a data structure input, remove ANSI sequences from strings at the given cell paths",
+                "For a data structure input, remove ANSI sequences from strings at the given cell paths.",
             )
             .allow_variants_without_examples(true)
             .category(Category::Platform)

crates/nu-command/src/platform/du.rs

@@ -38,7 +38,7 @@ impl Command for Du {
         Signature::build("du")
             .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
             .allow_variants_without_examples(true)
-            .optional("path", SyntaxShape::GlobPattern, "starting directory")
+            .optional("path", SyntaxShape::GlobPattern, "Starting directory.")
             .switch(
                 "all",
                 "Output file sizes as well as directory sizes",

crates/nu-command/src/platform/input/input_.rs

@@ -39,7 +39,7 @@ impl Command for Input {
                 (Type::Nothing, Type::Binary),
             ])
             .allow_variants_without_examples(true)
-            .optional("prompt", SyntaxShape::String, "prompt to show the user")
+            .optional("prompt", SyntaxShape::String, "Prompt to show the user.")
             .named(
                 "bytes-until-any",
                 SyntaxShape::String,

crates/nu-command/src/platform/input/list.rs

@@ -46,7 +46,7 @@ impl Command for InputList {
                 (Type::List(Box::new(Type::Any)), Type::Any),
                 (Type::Range, Type::Int),
             ])
-            .optional("prompt", SyntaxShape::String, "the prompt to display")
+            .optional("prompt", SyntaxShape::String, "The prompt to display.")
             .switch(
                 "multi",
                 "Use multiple results, you can press a to toggle all options on/off",

crates/nu-command/src/platform/kill.rs

@@ -26,9 +26,9 @@ impl Command for Kill {
             .required(
                 "pid",
                 SyntaxShape::Int,
-                "process id of process that is to be killed",
+                "Process id of process that is to be killed.",
             )
-            .rest("rest", SyntaxShape::Int, "rest of processes to kill")
+            .rest("rest", SyntaxShape::Int, "Rest of processes to kill.")
             .switch("force", "forcefully kill the process", Some('f'))
             .switch("quiet", "won't print anything to the console", Some('q'))
             .category(Category::Platform);

crates/nu-command/src/platform/sleep.rs

@@ -27,8 +27,8 @@ impl Command for Sleep {
     fn signature(&self) -> Signature {
         Signature::build("sleep")
             .input_output_types(vec![(Type::Nothing, Type::Nothing)])
-            .required("duration", SyntaxShape::Duration, "time to sleep")
-            .rest("rest", SyntaxShape::Duration, "additional time")
+            .required("duration", SyntaxShape::Duration, "Time to sleep.")
+            .rest("rest", SyntaxShape::Duration, "Additional time.")
             .category(Category::Platform)
     }