Remove no-longer-needed convert_env_values calls (#14681)

# Description

Takes advantage of #14591 to remove the now-necessary calls to
`convert_env_values()` that I added in #14249. The function is now just
called once to convert `PATH`.

Also removed the Windows-build-time checks for `ensure_path`, since
previous case-insensitivity fixes make this unnecessary as well.

# User-Facing Changes

None - #14591 now handles conversion 'on-demand'.

# Tests + Formatting

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

# After Submitting

N/A

crates/nu-cli/src/repl.rs

@@ -19,7 +19,7 @@ use miette::{ErrReport, IntoDiagnostic, Result};
 use nu_cmd_base::util::get_editor;
 use nu_color_config::StyleComputer;
 #[allow(deprecated)]
-use nu_engine::{convert_env_values, current_dir_str, env_to_strings};
+use nu_engine::{current_dir_str, env_to_strings};
 use nu_parser::{lex, parse, trim_quotes_str};
 use nu_protocol::{
     config::NuCursorShape,
@@ -81,13 +81,6 @@ pub fn evaluate_repl(
         stack.clone(),
     );
 
-    let start_time = std::time::Instant::now();
-    // Translate environment variables from Strings to Values
-    if let Err(e) = convert_env_values(engine_state, &unique_stack) {
-        report_shell_error(engine_state, &e);
-    }
-    perf!("translate env vars", start_time, use_color);
-
     // seed env vars
     unique_stack.add_env_var(
         "CMD_DURATION_MS".into(),

crates/nu-engine/src/env.rs

@@ -89,22 +89,7 @@ pub fn convert_env_values(engine_state: &mut EngineState, stack: &Stack) -> Resu
         }
     }
 
-    #[cfg(not(windows))]
-    {
-        error = error.or_else(|| ensure_path(&mut new_scope, "PATH"));
-    }
-
-    #[cfg(windows)]
-    {
-        let first_result = ensure_path(&mut new_scope, "Path");
-        if first_result.is_some() {
-            let second_result = ensure_path(&mut new_scope, "PATH");
-
-            if second_result.is_some() {
-                error = error.or(first_result);
-            }
-        }
-    }
+    error = error.or_else(|| ensure_path(&mut new_scope, "PATH"));
 
     if let Ok(last_overlay_name) = &stack.last_overlay_name() {
         if let Some(env_vars) = Arc::make_mut(&mut engine_state.env_vars).get_mut(last_overlay_name)

src/config_files.rs

@@ -51,18 +51,6 @@ pub(crate) fn read_config_file(
             use_color
         );
     } else {
-        let start_time = std::time::Instant::now();
-        let config = engine_state.get_config();
-        let use_color = config.use_ansi_coloring.get(engine_state);
-        if let Err(e) = convert_env_values(engine_state, stack) {
-            report_shell_error(engine_state, &e);
-        }
-        perf!(
-            "translate env vars before default_config.nu",
-            start_time,
-            use_color
-        );
-
         eval_default_config(engine_state, stack, get_default_config(), is_env_config);
     };