refactor: notify/footer 持久配置收编到 config/，chrome bridge 地址固定

仓库规则要求 config/ 为唯一配置来源、不以环境变量作持久默认值：
- pi-notify 改读 config/pi-notify.json（逐字段校验回退，复用原 parsers 钳制）
- pi-minimal-footer 改读 config/pi-minimal-footer.json
- pi-chrome 移除 PI_CHROME_BRIDGE_HOST/PORT，固定 127.0.0.1:17318
  （浏览器端 service_worker.js 硬编码同一地址，单侧可配只会断连）

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

pi-notify/tests/index.test.ts

@@ -1,23 +1,24 @@
 import assert from "node:assert/strict";
-import { afterEach, describe, it } from "node:test";
+import { describe, it } from "node:test";
 import type { ExtensionAPI, ExtensionContext } from "@earendil-works/pi-coding-agent";
 import { createPiNotifyExtension } from "../src/index.ts";
+import type { NotifySettings } from "../src/settings.ts";
 import type { NotifyConfig } from "../src/types.ts";
 
 type Handler = (...args: any[]) => any;
 
-const savedEnv = new Map(
-  ["PI_NOTIFY_MIN_SECONDS", "PI_NOTIFY_MESSAGE_SOURCE"].map((key) => [key, process.env[key]]),
-);
+const DEFAULT_SETTINGS: NotifySettings = {
+  enabled: true,
+  title: "π - {project}",
+  body: "{message}",
+  messageSource: "assistant",
+  messageMax: 80,
+  minDurationMs: 3_000,
+  visibility: "always",
+  action: "focus",
+};
 
-afterEach(() => {
-  for (const [key, value] of savedEnv) {
-    if (value === undefined) delete process.env[key];
-    else process.env[key] = value;
-  }
-});
-
-function harness(mode: ExtensionContext["mode"] = "tui") {
+function harness(mode: ExtensionContext["mode"] = "tui", settings: Partial<NotifySettings> = {}) {
   const handlers = new Map<string, Handler>();
   const eventHandlers = new Map<string, Handler>();
   const commands = new Map<string, { handler: Handler }>();
@@ -45,6 +46,7 @@ function harness(mode: ExtensionContext["mode"] = "tui") {
     createNotificationId: () => "pi-session-test",
     notify: (config) => notifications.push(config),
     getBackend: () => "kitty",
+    settings: { ...DEFAULT_SETTINGS, ...settings },
   })(pi);
 
   const ctx = {
@@ -93,9 +95,8 @@ describe("pi-notify extension", () => {
   });
 
   it("does not write terminal notifications in RPC or non-interactive modes", async () => {
-    process.env.PI_NOTIFY_MIN_SECONDS = "0";
     for (const mode of ["rpc", "json", "print"] as const) {
-      const h = harness(mode);
+      const h = harness(mode, { minDurationMs: 0 });
       await h.handlers.get("session_start")?.({}, h.ctx);
       await h.handlers.get("agent_start")?.({}, h.ctx);
       await h.handlers.get("agent_settled")?.({}, h.ctx);
@@ -123,8 +124,7 @@ describe("pi-notify extension", () => {
   });
 
   it("notifies immediately when permission confirmation needs human input", async () => {
-    process.env.PI_NOTIFY_MIN_SECONDS = "3600";
-    const h = harness();
+    const h = harness("tui", { minDurationMs: 3_600_000 });
     await h.handlers.get("session_start")?.({}, h.ctx);
 
     h.eventHandlers.get("permissions:ui_prompt")?.({
@@ -144,8 +144,7 @@ describe("pi-notify extension", () => {
   });
 
   it("keeps permission details private and honors the session off override", async () => {
-    process.env.PI_NOTIFY_MESSAGE_SOURCE = "none";
-    const h = harness();
+    const h = harness("tui", { messageSource: "none" });
     await h.handlers.get("session_start")?.({}, h.ctx);
     const prompt = { requestId: "perm-secret", surface: "bash", value: "cat private-file" };