windows-sandbox: remove SandboxPolicy runner plumbing (#23813)

## Why

The Windows sandbox runner still carried the old `SandboxPolicy`
compatibility path even though core now computes `PermissionProfile`.
That meant Windows command-runner execution could only see the legacy
projection, so profile-only filesystem rules such as deny globs were not
part of the runner input.

## What Changed

- Removed the Windows-local `SandboxPolicy` parser/export and deleted
`windows-sandbox-rs/src/policy.rs`.
- Changed restricted-token capture/session setup, elevated setup,
world-writable audit, read-root grant, and command-runner session APIs
to accept `PermissionProfile` plus the profile cwd.
- Bumped the elevated command-runner IPC protocol to version 2 because
`SpawnRequest` now carries `permission_profile` /
`permission_profile_cwd` instead of the legacy `policy_json_or_preset` /
`sandbox_policy_cwd` fields.
- Updated core exec, unified exec, debug-sandbox, TUI setup/grant flows,
and app-server setup to pass the actual effective `PermissionProfile`.
- Left regression coverage asserting the old IPC policy fields are
absent and the runner serializes tagged `PermissionProfile` JSON.

## Verification

- `cargo test -p codex-windows-sandbox`
- `cargo test -p codex-core windows_sandbox`
- `cargo test -p codex-app-server
request_processors::windows_sandbox_processor`
- `just fix -p codex-windows-sandbox -p codex-core -p codex-app-server
-p codex-cli -p codex-tui`
- `just fix -p codex-cli -p codex-tui`
- `just fix -p codex-windows-sandbox -p codex-tui`
- `rg "\\bSandboxPolicy\\b" codex-rs/windows-sandbox-rs` returned no
matches.

Note: `cargo test -p codex-cli` was attempted but did not reach crate
tests because local disk filled while compiling dependencies (`No space
left on device`). The targeted clippy pass compiled the affected CLI/TUI
surfaces afterward.




---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/23813).
* #24108
* __->__ #23813

codex-rs/core/src/unified_exec/process_manager.rs

@@ -866,12 +866,6 @@ impl UnifiedExecProcessManager {
 
         #[cfg(target_os = "windows")]
         if request.sandbox == codex_sandboxing::SandboxType::WindowsRestrictedToken {
-            let sandbox_policy = request.compatibility_sandbox_policy();
-            let policy_json = serde_json::to_string(&sandbox_policy).map_err(|err| {
-                UnifiedExecError::create_process(format!(
-                    "failed to serialize Windows sandbox policy: {err}"
-                ))
-            })?;
             let codex_home = crate::config::find_codex_home().map_err(|err| {
                 UnifiedExecError::create_process(format!(
                     "windows sandbox: failed to resolve codex_home: {err}"
@@ -923,7 +917,7 @@ impl UnifiedExecProcessManager {
                 codex_protocol::config_types::WindowsSandboxLevel::RestrictedToken
                 | codex_protocol::config_types::WindowsSandboxLevel::Disabled => {
                     codex_windows_sandbox::spawn_windows_sandbox_session_legacy(
-                        policy_json.as_str(),
+                        &request.permission_profile,
                         request.windows_sandbox_policy_cwd.as_path(),
                         codex_home.as_ref(),
                         request.command.clone(),