feat: add --download-path option (#536)

* feat: add --download-path option

Adds a `--download-path` flag (and `AGENT_BROWSER_DOWNLOAD_PATH` env / `downloadPath` config key) to set a default download directory for browser downloads.

Without this, Playwright stores downloads in a temp directory that is deleted when the browser closes. The new option passes through to Playwright's `downloadsPath` on `launch()` and `launchPersistentContext()`.

Fixes #507

* improvements

* fixes

* fixes

cli/src/connection.rs

@@ -220,6 +220,7 @@ pub fn ensure_daemon(
     provider: Option<&str>,
     device: Option<&str>,
     session_name: Option<&str>,
+    download_path: Option<&str>,
 ) -> Result<DaemonResult, String> {
     // Check if daemon is running AND responsive
     if is_daemon_running(session) && daemon_ready(session) {
@@ -364,6 +365,10 @@ pub fn ensure_daemon(
             cmd.env("AGENT_BROWSER_SESSION_NAME", sn);
         }
 
+        if let Some(dp) = download_path {
+            cmd.env("AGENT_BROWSER_DOWNLOAD_PATH", dp);
+        }
+
         // Create new process group and session to fully detach
         unsafe {
             cmd.pre_exec(|| {
@@ -447,6 +452,10 @@ pub fn ensure_daemon(
             cmd.env("AGENT_BROWSER_SESSION_NAME", sn);
         }
 
+        if let Some(dp) = download_path {
+            cmd.env("AGENT_BROWSER_DOWNLOAD_PATH", dp);
+        }
+
         // CREATE_NEW_PROCESS_GROUP | DETACHED_PROCESS
         const CREATE_NEW_PROCESS_GROUP: u32 = 0x00000200;
         const DETACHED_PROCESS: u32 = 0x00000008;