WEB Knobs in API

Co-Authored-By: brekotis <93345790+brekotis@users.noreply.github.com>

src/web/session.rs

@@ -24,6 +24,9 @@ mod backend;
 mod downlink;
 // Response ownership keeps detached batches charged until the last body clone drops.
 mod resident;
+// Read-only control-plane snapshots stay isolated from carrier operations.
+mod status;
+pub(crate) use status::WebSessionStatus;
 // Lane carrier state isolates request sequencing and downlink replay per logical stream.
 mod lanes;
 // Lane batch staging transfers queue ownership without escaping process budgets.
@@ -205,6 +208,7 @@ pub(crate) struct WebSession {
     carrier_class: CarrierClientClass,
     learning_context: Option<CarrierLearningContext>,
     automatic_carrier: bool,
+    created_at: Instant,
     limits: WebLimitsConfig,
     timeouts: WebTimeoutsConfig,
     state: Mutex<SessionState>,
@@ -268,6 +272,7 @@ impl WebSession {
             carrier_class,
             learning_context,
             automatic_carrier,
+            created_at: Instant::now(),
             limits,
             timeouts,
             state: Mutex::new(SessionState {
@@ -344,6 +349,11 @@ impl WebSession {
         self.trace_session_id
     }
 
+    /// Returns the immutable carrier-attempt incarnation number.
+    pub(crate) fn carrier_attempt(&self) -> u8 {
+        self.carrier_attempt
+    }
+
     /// Creates a child cancellation boundary for one owned carrier task.
     pub(crate) fn carrier_cancellation(&self) -> CancellationToken {
         self.cancel.child_token()