feat: added WebSocket transport support for OpenAI Codex with SSE fallback

- Added WebSocket transport support for OpenAI Codex responses with automatic fallback to SSE on connection failure.
- Added preferWebsockets option to Agent and Model configurations to hint that WebSocket transport should be preferred when supported by provider implementations.
- Added prewarmOpenAICodexResponses() function to pre-establish WebSocket connections for improved performance.
- Added getProviderDetails() function and getOpenAICodexTransportDetails() function to expose transport state and provider configuration information.
- Added provider details display in session info showing active provider configuration and authentication details.
- Added OpenAI websockets setting to enable WebSocket transport preference for OpenAI Codex models in coding agent configuration.

packages/coding-agent/test/session-provider-section.test.ts

@@ -0,0 +1,34 @@
+import { describe, expect, it } from "bun:test";
+import { getProviderDetails, type Model } from "@oh-my-pi/pi-ai";
+import { renderProviderSection } from "@oh-my-pi/pi-coding-agent/modes/controllers/command-controller";
+describe("session provider section", () => {
+	it("renders codex provider details with transport fields", () => {
+		const model: Model<"openai-codex-responses"> = {
+			id: "gpt-5.3-codex-spark",
+			name: "GPT-5.3 Codex Spark",
+			api: "openai-codex-responses",
+			provider: "openai-codex",
+			baseUrl: "https://chatgpt.com/backend-api",
+			reasoning: true,
+			preferWebsockets: true,
+			input: ["text"],
+			cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
+			contextWindow: 128000,
+			maxTokens: 128000,
+		};
+
+		const details = getProviderDetails({
+			model,
+			sessionId: "session-1",
+			authMode: "oauth",
+		});
+		const output = renderProviderSection(details, { fg: (_color: string, text: string) => text });
+
+		expect(output).toContain("Name:");
+		expect(output).toContain("openai-codex");
+		expect(output).toContain("Transport:");
+		expect(output).toContain("WebSocket:");
+		expect(output).toContain("Reuse:");
+		expect(output).toContain("Auth:");
+	});
+});