Route sandbox CLI launches through the shared sandbox manager (#60517)

## What changed

- Use `SandboxManager` to prepare `codex sandbox` commands, including permission profiles, workspace roots, and managed network proxy settings.
- Return a `WrappedSandboxCommand` that can produce an execution request or a configured process command, preserving native executable paths and Linux helper `argv[0]`. Require the session launcher for native Windows token sandboxes.
- Move macOS inherited-terminal policy handling into the shared manager, retaining Unix socket grants and the terminal input injection denial.
- Prepare managed network context alongside proxy environment variables and pass it through sandbox transformation.

## Testing

- Extend sandbox network proxy tests to macOS, covering blocked direct loopback access and explicitly allowed requests.
- Add coverage for Linux helper executable paths and dispatch names, including non-UTF-8 paths.

GitOrigin-RevId: 8b7396d21b2f34122699388f16047329a3f5e5c6

codex-rs/core/src/tools/sandboxing.rs

@@ -513,8 +513,8 @@ impl<'a> SandboxAttempt<'a> {
                 sandbox_exe: self.sandbox_exe.map(std::path::PathBuf::as_path),
                 use_legacy_landlock: self.use_legacy_landlock,
                 windows_sandbox_level: self.windows_sandbox_level,
-            })
-            .map_err(CodexErr::from)?;
+            })?
+            .into_command_request();
         request.sandbox_override = self.sandbox_override;
         let workspace_roots = self
             .workspace_roots
@@ -550,8 +550,8 @@ impl<'a> SandboxAttempt<'a> {
                 sandbox_exe: None,
                 use_legacy_landlock: self.use_legacy_landlock,
                 windows_sandbox_level: self.windows_sandbox_level,
-            })
-            .map_err(CodexErr::from)?;
+            })?
+            .into_command_request();
         request.sandbox_override = self.sandbox_override;
         let mut exec_request =
             crate::sandboxing::ExecRequest::from_sandbox_exec_request(request, options, Vec::new())