fix(session): increase default session timeout to 1 week

Changed the default session timeout from 1 hour (3600s) to 1 week (604800s)
in both cortex-app-server config and cortex-engine state defaults.

Author: echobt

src/cortex-app-server/src/config.rs

@@ -331,7 +331,7 @@ fn default_max_sessions() -> usize {
 }
 
 fn default_session_timeout() -> u64 {
-    3600 // 1 hour
+    604800 // 1 week
 }
 
 fn default_max_messages() -> usize {

src/cortex-engine/src/state/mod.rs

@@ -69,7 +69,7 @@ impl Default for StateConfig {
     fn default() -> Self {
         Self {
             max_sessions: 100,
-            session_timeout: Duration::from_secs(3600),
+            session_timeout: Duration::from_secs(604800), // 1 week
             turn_timeout: Duration::from_secs(300),
             persist: false,
             persist_dir: None,