core tests: build user turns from permission profiles (#20011)

## Summary
- Add `turn_permission_fields()` so tests that construct `Op::UserTurn`
directly can provide a canonical `PermissionProfile` while still filling
the required legacy `sandbox_policy` compatibility field.
- Migrate direct user-turn construction in core integration tests from
`SandboxPolicy::DangerFullAccess` to `PermissionProfile::Disabled`.
- Continue reducing direct `SandboxPolicy` usage in
`codex-rs/core/tests`, from 41 files after #20010 to 32 files in this
PR.

## Testing
- `cargo check -p codex-core --tests`
- `just fmt`
- `just fix -p core_test_support`
- `just fix -p codex-core`

codex-rs/core/tests/suite/websocket_fallback.rs

@@ -1,9 +1,9 @@
 use anyhow::Result;
 use codex_model_provider_info::WireApi;
+use codex_protocol::models::PermissionProfile;
 use codex_protocol::protocol::AskForApproval;
 use codex_protocol::protocol::EventMsg;
 use codex_protocol::protocol::Op;
-use codex_protocol::protocol::SandboxPolicy;
 use codex_protocol::user_input::UserInput;
 use core_test_support::responses;
 use core_test_support::responses::ev_completed;
@@ -14,6 +14,7 @@ use core_test_support::responses::sse;
 use core_test_support::skip_if_no_network;
 use core_test_support::test_codex::TestCodex;
 use core_test_support::test_codex::test_codex;
+use core_test_support::test_codex::turn_permission_fields;
 use pretty_assertions::assert_eq;
 use tokio::time::Duration;
 use tokio::time::timeout;
@@ -147,6 +148,8 @@ async fn websocket_fallback_hides_first_websocket_retry_stream_error() -> Result
         cwd,
         ..
     } = builder.build(&server).await?;
+    let (sandbox_policy, permission_profile) =
+        turn_permission_fields(PermissionProfile::Disabled, cwd.path());
 
     codex
         .submit(Op::UserTurn {
@@ -159,8 +162,8 @@ async fn websocket_fallback_hides_first_websocket_retry_stream_error() -> Result
             cwd: cwd.path().to_path_buf(),
             approval_policy: AskForApproval::Never,
             approvals_reviewer: None,
-            sandbox_policy: SandboxPolicy::DangerFullAccess,
-            permission_profile: None,
+            sandbox_policy,
+            permission_profile,
             model: session_configured.model.clone(),
             effort: None,
             summary: None,