fix(config): brand-compat config dir (~/.chrome-use ⇄ ~/.agent-browser) so the relay survives the rename

After the agent-browser → chrome-use rename, the new binary used ~/.chrome-use
+ host com.leeguoo.chrome_use and couldn't find the relay that the still-old
native-messaging host wrote to ~/.agent-browser → it fell back to raw
--remote-debugging-port and re-popped 'Allow remote debugging?'.

- config_home()/config_dir_basename(): decide once per run — prefer the new
  .chrome-use, but keep using an existing .agent-browser install if that's the
  only one present; fresh installs get .chrome-use. get_socket_dir() routes
  through it so sockets/state are consistent within a run.
- relay_url_path(): the relay-cdp-url is a cross-binary handoff (host writes,
  CLI reads), so read from whichever brand dir actually has the file
  (~/.chrome-use OR ~/.agent-browser).

Combined with keeping HOST_NAME=com.agent_browser.connect (b6febbe), the renamed
chrome-use binary now relays through the existing ab-connect 0.4.2 extension
with zero dialog. Verified live: chrome-use found ~/.agent-browser/relay-cdp-url
and listed the user's real tabs, no consent dialog.

cli/src/connect.rs

@@ -399,10 +399,23 @@ fn random_guid() -> String {
 }
 
 /// Where the daemon/CLI reads the relay's CDP WebSocket URL (perms 600).
+///
+/// Cross-binary handoff: the native-messaging *host* writes it and the CLI reads
+/// it, but the two may be different binaries under different brand dirs after
+/// the agent-browser → chrome-use rename. Read from whichever brand dir actually
+/// has the file (an old `agent-browser` host writes `~/.agent-browser`; a
+/// `chrome-use` host writes `~/.chrome-use`); default to [`config_home`].
 fn relay_url_path() -> PathBuf {
-    dirs::home_dir()
-        .map(|h| h.join(".chrome-use").join("relay-cdp-url"))
-        .unwrap_or_else(|| PathBuf::from("/tmp/ab-relay-cdp-url"))
+    if let Some(home) = dirs::home_dir() {
+        for base in [".chrome-use", ".agent-browser"] {
+            let p = home.join(base).join("relay-cdp-url");
+            if p.exists() {
+                return p;
+            }
+        }
+        return crate::connection::config_home().join("relay-cdp-url");
+    }
+    PathBuf::from("/tmp/ab-relay-cdp-url")
 }
 
 /// The live relay CDP WebSocket URL, if the native-messaging host is running