unified-exec: retain PathUri in command events (#28780)

## Why

App-server must report command events containing foreign-platform paths
without changing existing client or rollout path-string formats.

## What changed

- retain `PathUri` through exec command begin/end events
- convert cwd values to `LegacyAppPathString` at the app-server
compatibility boundary
- drop command actions with foreign paths and log them
- serialize rollout-trace cwd values using their inferred native path
representation
- restore Wine coverage for retained Windows cwd values and successful
completion

codex-rs/app-server/tests/suite/v2/turn_start.rs

@@ -2440,7 +2440,7 @@ async fn turn_start_updates_sandbox_and_cwd_between_turns_v2() -> Result<()> {
     else {
         unreachable!("loop ensures we break on command execution items");
     };
-    assert_eq!(cwd.as_path(), second_cwd.as_path());
+    assert_eq!(cwd.as_str(), second_cwd.to_string_lossy().as_ref());
     let expected_command = format_with_current_shell_display("echo second turn");
     assert_eq!(command, expected_command);
     assert_eq!(status, CommandExecutionStatus::InProgress);

codex-rs/app-server/tests/suite/v2/turn_start_zsh_fork.rs

@@ -167,7 +167,7 @@ async fn turn_start_shell_zsh_fork_executes_command_v2() -> Result<()> {
     assert!(command.contains("/bin/sh -c"));
     assert!(command.contains("sleep 0.01"));
     assert!(command.contains(&release_marker.display().to_string()));
-    assert_eq!(cwd.as_path(), workspace.as_path());
+    assert_eq!(cwd.as_str(), workspace.to_string_lossy().as_ref());
 
     mcp.interrupt_turn_and_wait_for_aborted(thread.id, turn.id, DEFAULT_READ_TIMEOUT)
         .await?;