Avoid taking unnecessary ownership of intermediates (#12740)

# Description

Judiciously try to avoid allocations/clone by changing the signature of
functions

- **Don't pass str by value unnecessarily if only read**
- **Don't require a vec in `Sandbox::with_files`**
- **Remove unnecessary string clone**
- **Fixup unnecessary borrow**
- **Use `&str` in shape color instead**
- **Vec -> Slice**
- **Elide string clone**
- **Elide `Path` clone**
- **Take &str to elide clone in tests**

# User-Facing Changes
None

# Tests + Formatting
This touches many tests purely in changing from owned to borrowed/static
data

crates/nu-table/src/types/general.rs

@@ -99,7 +99,7 @@ fn table(input: &[Value], opts: &TableOpts<'_>) -> TableResult {
         .filter(|header| header != INDEX_COLUMN_NAME)
         .collect();
 
-    let table = to_table_with_header(input, headers, with_index, row_offset, opts)?;
+    let table = to_table_with_header(input, &headers, with_index, row_offset, opts)?;
     let table = table.map(|table| TableOutput::new(table, true, with_index));
 
     Ok(table)
@@ -107,7 +107,7 @@ fn table(input: &[Value], opts: &TableOpts<'_>) -> TableResult {
 
 fn to_table_with_header(
     input: &[Value],
-    headers: Vec<String>,
+    headers: &[String],
     with_index: bool,
     row_offset: usize,
     opts: &TableOpts<'_>,