Add SPA session validation and buglist, update migration docs

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Co-Authored-By: Claude <noreply@anthropic.com>

app/RSpade/Integrations/Jqhtml/Jqhtml_Integration.js

@@ -49,11 +49,22 @@ class Jqhtml_Integration {
         // ─────────────────────────────────────────────────────────────────────
         // Tag Static Methods with Cache IDs
         //
-        // jqhtml caches component output based on args. When a function is passed
-        // as an arg (e.g., DataGrid's data_source), we need a stable string key.
+        // jqhtml caches component renders based on a hash of their args.
+        // Problem: Functions can't be serialized, so passing one (e.g., a
+        // DataGrid's data_source callback) would defeat caching entirely.
         //
-        // Without this: data_source: function() {...} → no cache (functions aren't serializable)
-        // With this:    function._jqhtml_cache_id = "My_DataGrid.fetch_data" → cacheable
+        // Solution: Tag every static method with a stable string identifier.
+        // When jqhtml hashes component args, it uses _jqhtml_cache_id instead
+        // of the function reference, making the cache key deterministic.
+        //
+        // Example:
+        //   <My_DataGrid $data_source=Controller.fetch />
+        //
+        //   Without tagging: args hash includes [Function] → uncacheable
+        //   With tagging:    args hash includes "Controller.fetch" → cacheable
+        //
+        // This enables Ajax endpoints and other callbacks to be passed to
+        // components without breaking the automatic caching system.
         // ─────────────────────────────────────────────────────────────────────
         const all_classes = Manifest.get_all_classes();
         let methods_tagged = 0;
@@ -106,20 +117,6 @@ class Jqhtml_Integration {
             Rsx.trigger('jqhtml_ready');
         });
     }
-
-    // ═══════════════════════════════════════════════════════════════════════
-    // Utility Methods (pass-through to jqhtml runtime)
-    // ═══════════════════════════════════════════════════════════════════════
-
-    /** Get all registered component names. Useful for debugging/introspection. */
-    static get_component_names() {
-        return jqhtml.get_component_names();
-    }
-
-    /** Check if a component is registered by name. */
-    static has_component(name) {
-        return jqhtml.has_component(name);
-    }
 }
 
 // Class is automatically made global by RSX manifest - no window assignment needed