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/analytics/src/analytics_client_tests.rs

@@ -831,7 +831,7 @@ fn sample_command_execution_item_with_id(
     ThreadItem::CommandExecution {
         id: id.to_string(),
         command: "echo hi".to_string(),
-        cwd: test_path_buf("/tmp").abs(),
+        cwd: test_path_buf("/tmp").abs().into(),
         process_id: Some("pid-1".to_string()),
         source: CommandExecutionSource::Agent,
         status,