Enable git attribution across Codex entry points (#34819)

## What changed

- Install the git attribution extension in the app server, MCP server, and `codex debug prompt-input` so authenticated workspace policy controls the commit and pull request attribution instructions sent to the model.
- Resolve attribution settings from the process-level ChatGPT base URL, independent of per-thread or per-tool configuration overrides.
- Treat git attribution as contextual developer content when mapping model events.

## Testing

- Cover policy fetch retries, workspace switches, rollbacks, cold thread resumes with legacy instructions, MCP tool calls, and prompt-debug output.

GitOrigin-RevId: 57d182c432c20d7c1c6c429057b6163c9f32088d

codex-rs/cli/src/main.rs

@@ -1999,10 +1999,20 @@ async fn run_debug_prompt_input_command(
     let user_instructions_provider = Arc::new(CodexHomeUserInstructionsProvider::new(
         config.codex_home.clone(),
     ));
+    let auth_manager =
+        AuthManager::shared_from_config(&config, /*enable_codex_api_key_env*/ false).await;
+    let mut extensions = codex_extension_api::ExtensionRegistryBuilder::new();
+    codex_git_attribution::install(
+        &mut extensions,
+        auth_manager,
+        config.chatgpt_base_url.clone(),
+        config.http_client_factory(),
+    );
     let prompt_input = codex_core::build_prompt_input(
         config,
         input,
         /*state_db*/ None,
+        Arc::new(extensions.build()),
         user_instructions_provider,
     )
     .await?;