Move more commands to opaque Record type (#11122)

# Description

Further work towards the goal that we can make `Record`'s field private
and experiment with different internal representations

## Details
- Use inplace record iter in `nu-command/math/utils`
  - Guarantee that existing allocation can be reused
- Use proper record iterators in `path join`
- Remove unnecesary hashmap in `path join`
  - Should minimally reduce the overhead
- Unzip records in `nu-command`
- Refactor `query web` plugin to use record APIs
- Use `Record::into_values` for `values` command
- Use `Record::columns()` in `join` instead.
  - Potential minor pessimisation
  - Not the hot value path
- Use sane `Record` iters in example `Debug` impl
- Avoid layout assumption in `nu-cmd-extra/roll/mod`
  - Potential minor pessimisation
- relegated to `extra`, changing the representation may otherwise break
this op.
- Use record api in `rotate`
- Minor risk that this surfaces some existing invalid behavior as panics
as we now validate column/value lengths
  - `extra` so things are unstable
- Remove unnecessary references in `rotate`
  - Bonus cleanup
# User-Facing Changes
None functional, minor potential differences in runtime. You win some,
you lose some.

# Tests + Formatting
Relying on existing tests

crates/nu_plugin_query/src/query_web.rs

@@ -180,26 +180,21 @@ fn retrieve_table(mut table: WebTable, columns: &Value, span: Span) -> Value {
         table_out.push(Value::record(record, span))
     } else {
         for row in &table {
-            let mut vals = vec![];
-            let record_cols = &cols;
-            for col in &cols {
-                let val = row
-                    .get(col)
-                    .unwrap_or(&format!("Missing column: '{}'", &col))
-                    .to_string();
+            let record = cols
+                .iter()
+                .map(|col| {
+                    let val = row
+                        .get(col)
+                        .unwrap_or(&format!("Missing column: '{}'", &col))
+                        .to_string();
 
-                if !at_least_one_row_filled && val != format!("Missing column: '{}'", &col) {
-                    at_least_one_row_filled = true;
-                }
-                vals.push(Value::string(val, span));
-            }
-            table_out.push(Value::record(
-                Record {
-                    cols: record_cols.to_vec(),
-                    vals,
-                },
-                span,
-            ))
+                    if !at_least_one_row_filled && val != format!("Missing column: '{}'", &col) {
+                        at_least_one_row_filled = true;
+                    }
+                    (col.clone(), Value::string(val, span))
+                })
+                .collect();
+            table_out.push(Value::record(record, span))
         }
     }
     if !at_least_one_row_filled {