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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pi-minimal-footer/index.ts

@@ -15,6 +15,7 @@ import { existsSync, readFileSync } from "node:fs";
 import { join } from "node:path";
 import { homedir } from "node:os";
 import { collectFooterStatusItems } from "./status.ts";
+import { readFooterSettings } from "./settings.ts";
 
 // ============ Types ============
 
@@ -43,19 +44,6 @@ interface GitCache {
 const USAGE_REFRESH_INTERVAL = 5 * 60_000; // 5 minutes
 const usageCache = new Map<string, UsageSnapshot>(); // keyed by provider
 
-// ============ Env Flags ============
-
-function parseBooleanEnv(value: string | undefined, fallback: boolean): boolean {
-  if (value === undefined) return fallback;
-
-  const normalized = value.trim().toLowerCase();
-  if (!normalized) return fallback;
-
-  if (["1", "true", "yes", "on"].includes(normalized)) return true;
-  if (["0", "false", "no", "off"].includes(normalized)) return false;
-  return fallback;
-}
-
 // ============ Identity Cache ============
 
 let codexEmailPrefix: string | null | undefined; // undefined = not yet resolved
@@ -754,9 +742,8 @@ export default function (pi: ExtensionAPI) {
   const BAR_FILLED = "━";
   const BAR_EMPTY = "─";
 
-  // Optional visibility toggles (default: enabled)
-  const showCwd = parseBooleanEnv(process.env.PI_MINIMAL_FOOTER_SHOW_CWD, true);
-  const showBranch = parseBooleanEnv(process.env.PI_MINIMAL_FOOTER_SHOW_BRANCH, true);
+  // Optional visibility toggles from bundle config (default: enabled)
+  const { showCwd, showBranch } = readFooterSettings();
 
   function formatTokenCount(tokens: number): string {
     if (tokens >= 1_000_000) {