feat(web): App.UploadChatModels -- the models upload chat offers and accepts (review F1)

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

internal/web/handlers.go

@@ -122,6 +122,11 @@ type App struct {
 	// summarizer's (koala/phi4-mini, 8,192-token context) and cannot hold an hour of
 	// speech.
 	UploadChatModel string
+	// UploadChatModels is the set of models chat over an uploaded recording offers and
+	// accepts. The whole private transcript goes to the one chosen, so it must hold
+	// LOCAL models only, and the caller decides that. Nil or empty fails closed: no
+	// model is offered and none is called (ADR-035 review).
+	UploadChatModels []string
 	// Processing tracks in-flight immediate summarizations so the status endpoint
 	// shows the animation until the summary lands. The zero value is ready to use.
 	Processing ProcessingSet