refactor: implemented $PWD > cwd to prevent macOS symlink resolution

- Replaced all direct `process.cwd()` calls with `getProjectDir()` utility function across 40+ files to centralize project directory resolution logic.
- Added `getProjectDir()` and `setProjectDir()` functions to `@oh-my-pi/pi-utils/dirs` module to provide abstracted project directory management.
- Made `SessionManager.list()` method asynchronous to support asynchronous session discovery operations.
- Updated default working directory resolution throughout codebase to use `getProjectDir()` instead of `process.cwd()` for improved project directory detection.

packages/coding-agent/src/debug/system-info.ts

@@ -2,7 +2,7 @@
  * System information collection for debug reports.
  */
 import * as os from "node:os";
-import { VERSION } from "@oh-my-pi/pi-utils/dirs";
+import { getProjectDir, VERSION } from "@oh-my-pi/pi-utils/dirs";
 
 export interface SystemInfo {
 	os: string;
@@ -65,7 +65,7 @@ export async function collectSystemInfo(): Promise<SystemInfo> {
 			bun: Bun.version,
 			node: process.version,
 		},
-		cwd: process.cwd(),
+		cwd: getProjectDir(),
 		shell,
 		terminal,
 	};