fix(coding-agent): restored subagent thinking precedence

Agent frontmatter thinkingLevel now wins over model role suffix thinking when both are configured.

Fixes #3915

packages/coding-agent/test/task/executor-pass-through.test.ts

@@ -4,6 +4,9 @@
  * paid for. Regression guard for issue #2190.
  */
 import { afterEach, describe, expect, it, vi } from "bun:test";
+import { ThinkingLevel } from "@oh-my-pi/pi-agent-core";
+import type { Model } from "@oh-my-pi/pi-ai";
+import { getBundledModel } from "@oh-my-pi/pi-catalog/models";
 import type { Rule } from "@oh-my-pi/pi-coding-agent/capability/rule";
 import type { ModelRegistry } from "@oh-my-pi/pi-coding-agent/config/model-registry";
 import { Settings } from "@oh-my-pi/pi-coding-agent/config/settings";
@@ -89,6 +92,15 @@ const baseOptions = {
 	enableLsp: false,
 };
 
+function createModelRegistry(model: Model): ModelRegistry {
+	return {
+		authStorage: {},
+		refresh: async () => {},
+		getAvailable: () => [model],
+		getApiKey: async () => "test-key",
+	} as unknown as ModelRegistry;
+}
+
 describe("runSubprocess parent-discovery pass-through (issue #2190)", () => {
 	afterEach(() => {
 		vi.restoreAllMocks();
@@ -152,4 +164,26 @@ describe("runSubprocess parent-discovery pass-through (issue #2190)", () => {
 		expect(forwarded?.agentId).toBe("ChildAgent");
 		expect(forwarded?.parentTaskPrefix).toBe("ChildAgent");
 	});
+
+	it("lets agent frontmatter thinkingLevel override a task role suffix", async () => {
+		const model = getBundledModel("anthropic", "claude-sonnet-4-5");
+		if (!model) throw new Error("Expected claude-sonnet-4-5 model to exist");
+		const settings = Settings.isolated();
+		settings.setModelRole("task", `${model.provider}/${model.id}:high`);
+		const session = yieldEmittingSession();
+		const spy = vi.spyOn(sdkModule, "createAgentSession").mockResolvedValue(createSessionResult(session));
+
+		const result = await runSubprocess({
+			...baseOptions,
+			agent: { ...baseAgent, model: ["pi/task"] },
+			id: "subagent-thinking-precedence",
+			settings,
+			modelRegistry: createModelRegistry(model),
+			thinkingLevel: ThinkingLevel.Low,
+		});
+
+		expect(result.exitCode).toBe(0);
+		const forwarded = spy.mock.calls[0]?.[0];
+		expect(forwarded?.thinkingLevel).toBe(ThinkingLevel.Low);
+	});
 });