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-command/src/math/abs.rs

@@ -46,7 +46,7 @@ impl Command for SubCommand {
             result: Some(Value::List {
                 vals: vec![
                     Value::test_int(50),
-                    Value::float(100.0, Span::test_data()),
+                    Value::test_float(100.0),
                     Value::test_int(25),
                 ],
                 span: Span::test_data(),

crates/nu-command/src/math/avg.rs

@@ -40,7 +40,7 @@ impl Command for SubCommand {
         vec![Example {
             description: "Compute the average of a list of numbers",
             example: "[-50 100.0 25] | math avg",
-            result: Some(Value::float(25.0, Span::test_data())),
+            result: Some(Value::test_float(25.0)),
         }]
     }
 }

crates/nu-command/src/math/eval.rs

@@ -47,7 +47,7 @@ impl Command for SubCommand {
         vec![Example {
             description: "Evaluate math in the pipeline",
             example: "'10 / 4' | math eval",
-            result: Some(Value::float(2.5, Span::test_data())),
+            result: Some(Value::test_float(2.5)),
         }]
     }
 }

crates/nu-command/src/math/median.rs

@@ -46,7 +46,7 @@ impl Command for SubCommand {
             Example {
                 description: "Compute the median of a list of numbers",
                 example: "[3 8 9 12 12 15] | math median",
-                result: Some(Value::float(10.5, Span::test_data())),
+                result: Some(Value::test_float(10.5)),
             },
             Example {
                 description: "Compute the medians of the columns of a table",

crates/nu-command/src/math/round.rs

@@ -68,9 +68,9 @@ impl Command for SubCommand {
                 example: "[1.555 2.333 -3.111] | math round -p 2",
                 result: Some(Value::List {
                     vals: vec![
-                        Value::float(1.56, Span::test_data()),
-                        Value::float(2.33, Span::test_data()),
-                        Value::float(-3.11, Span::test_data()),
+                        Value::test_float(1.56),
+                        Value::test_float(2.33),
+                        Value::test_float(-3.11),
                     ],
                     span: Span::test_data(),
                 }),

crates/nu-command/src/math/stddev.rs

@@ -54,12 +54,12 @@ impl Command for SubCommand {
             Example {
                 description: "Compute the standard deviation of a list of numbers",
                 example: "[1 2 3 4 5] | math stddev",
-                result: Some(Value::float(std::f64::consts::SQRT_2, Span::test_data())),
+                result: Some(Value::test_float(std::f64::consts::SQRT_2)),
             },
             Example {
                 description: "Compute the sample standard deviation of a list of numbers",
                 example: "[1 2 3 4 5] | math stddev -s",
-                result: Some(Value::float(1.5811388300841898, Span::test_data())),
+                result: Some(Value::test_float(1.5811388300841898)),
             },
         ]
     }

crates/nu-command/src/math/variance.rs

@@ -46,12 +46,12 @@ impl Command for SubCommand {
             Example {
                 description: "Get the variance of a list of numbers",
                 example: "[1 2 3 4 5] | math variance",
-                result: Some(Value::float(2.0, Span::test_data())),
+                result: Some(Value::test_float(2.0)),
             },
             Example {
                 description: "Get the sample variance of a list of numbers",
                 example: "[1 2 3 4 5] | math variance -s",
-                result: Some(Value::float(2.5, Span::test_data())),
+                result: Some(Value::test_float(2.5)),
             },
         ]
     }