Further cleanup of Span::test_data usage + span fixes (#7595)

# Description

Inspired by #7592

For brevity use `Value::test_{string,int,float,bool}`

Includes fixes to commands that were abusing `Span::test_data` in their
implementation. Now the call span is used where possible or the explicit
`Span::unknonw` is used.

## Command fixes
- Fix abuse of `Span::test_data()` in `query_xml`
- Fix abuse of `Span::test_data()` in `term size`
- Fix abuse of `Span::test_data()` in `seq date`
- Fix two abuses of `Span::test_data` in `nu-cli`
- Change `Span::test_data` to `Span::unknown` in `keybindings listen`
- Add proper call span to `registry query`
- Fix span use in `nu_plugin_query`
- Fix span assignment in `select`
- Use `Span::unknown` instead of `test_data` in more places

## Other
- Use `Value::test_int`/`test_float()` consistently
- More `test_string` and `test_bool`
- Fix unused imports


# User-Facing Changes

Some commands may now provide more helpful spans for downstream use in
errors

crates/nu-cli/src/reedline_config.rs

@@ -7,8 +7,7 @@ use nu_parser::parse;
 use nu_protocol::{
     create_menus,
     engine::{EngineState, Stack, StateWorkingSet},
-    extract_value, Config, IntoPipelineData, ParsedKeybinding, ParsedMenu, PipelineData,
-    ShellError, Span, Value,
+    extract_value, Config, ParsedKeybinding, ParsedMenu, PipelineData, ShellError, Span, Value,
 };
 use reedline::{
     default_emacs_keybindings, default_vi_insert_keybindings, default_vi_normal_keybindings,
@@ -110,7 +109,7 @@ pub(crate) fn add_menus(
             };
 
             let mut temp_stack = Stack::new();
-            let input = Value::nothing(Span::test_data()).into_pipeline_data();
+            let input = PipelineData::Empty;
             let res = eval_block(&engine_state, &mut temp_stack, &block, input, false, false)?;
 
             if let PipelineData::Value(value, None) = res {

crates/nu-cli/src/repl.rs

@@ -639,7 +639,7 @@ pub fn eval_string_with_input(
         false,
         true,
     )
-    .map(|x| x.into_value(Span::test_data()))
+    .map(|x| x.into_value(Span::unknown()))
 }
 
 pub fn get_command_finished_marker(stack: &Stack, engine_state: &EngineState) -> String {