tui: carry permission profiles on user turns (#18285)

## Why

Per-turn permission overrides should use the same canonical profile
abstraction as session configuration. That lets TUI submissions preserve
exact configured permissions without round-tripping through legacy
sandbox fields.

## What changed

This adds `permission_profile` to user-turn operations, threads it
through TUI/app-server submission paths, fills the new field in existing
test fixtures, and adds coverage that composer submission includes the
configured profile.

## Verification

- `cargo test -p codex-tui permissions -- --nocapture`
- `cargo test -p codex-core --test all permissions_messages --
--nocapture`























































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[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/18285).
* #18288
* #18287
* #18286
* __->__ #18285

codex-rs/tui/src/app/thread_routing.rs

@@ -497,6 +497,7 @@ impl App {
                 approval_policy,
                 approvals_reviewer,
                 sandbox_policy,
+                permission_profile,
                 model,
                 effort,
                 summary,
@@ -571,14 +572,6 @@ impl App {
                     }
                 }
                 if should_start_turn {
-                    let permission_profile = if !app_server.is_remote()
-                        && self.runtime_sandbox_policy_override.is_some()
-                        && !matches!(sandbox_policy, SandboxPolicy::ExternalSandbox { .. })
-                    {
-                        Some(self.config.permissions.permission_profile())
-                    } else {
-                        None
-                    };
                     app_server
                         .turn_start(
                             thread_id,
@@ -588,7 +581,7 @@ impl App {
                             approvals_reviewer
                                 .unwrap_or(self.chat_widget.config_ref().approvals_reviewer),
                             sandbox_policy.clone(),
-                            permission_profile,
+                            permission_profile.clone(),
                             model.to_string(),
                             effort,
                             *summary,