feat: cherry-pick PR #183 — multi-provider support, PWA, dynamic models, UI improvements

Cherry-picked from decolua/9router PR #183.
Note: open-sse changes included but need further review due to extensive modifications.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/sse/services/model.js

@@ -40,6 +40,15 @@ export async function getModelInfo(modelStr) {
     };
   }
 
+  // Check if this is a combo name before resolving as alias
+  // This prevents combo names from being incorrectly routed to providers
+  const combo = await getComboByName(parsed.model);
+  if (combo) {
+    // Return null provider to signal this should be handled as combo
+    // The caller (handleChat) will detect this and handle it as combo
+    return { provider: null, model: parsed.model };
+  }
+
   return getModelInfoCore(modelStr, getModelAliases);
 }
 
@@ -50,7 +59,7 @@ export async function getModelInfo(modelStr) {
 export async function getComboModels(modelStr) {
   // Only check if it's not in provider/model format
   if (modelStr.includes("/")) return null;
-  
+
   const combo = await getComboByName(modelStr);
   if (combo && combo.models && combo.models.length > 0) {
     return combo.models;