Frontend audit: Bug fixes and refinements (#2112)

* (fix:attachements) sep id for redux ops

* (fix:ui) popups, toast, share modal

* (feat:agentsPreview) stable preview, ui fixes

* (fix:ui) light theme icon, sleek scroll

* (chore:i18n) missin keys

* (chore:i18n) missing keys

* (feat:preferrenceSlice) autoclear invalid source from storage

* (fix:general) delete all conv close btn

* (fix:tts) play one at a time

* (fix:tts) gracefully unmount

* (feat:tts) audio LRU cache

* (feat:tts) pointer on hovered area

* (feat:tts) clean text for speach

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Co-authored-by: GH Action - Upstream Sync <action@github.com>

frontend/src/agents/SharedAgent.tsx

@@ -144,7 +144,7 @@ export default function SharedAgent() {
             className="mx-auto mb-6 h-32 w-32"
           />
           <p className="dark:text-gray-4000 text-center text-lg text-[#71717A]">
-            No agent found. Please ensure the agent is shared.
+            {t('agents.shared.notFound')}
           </p>
         </div>
       </div>