At the start of this century, it was commonplace to say there were no good restaurants on the Upper West Side. It was wrong then and is even more wrong now, as new places open up. A cluster of Chinese restaurants have popped up on the northernmost edge of the neighborhood, new kosher and halal places are surging, and pizzerias offer arcane styles rarely seen in the city. Meanwhile, Mexican restaurants with affordable and more upscale menus dot the landscape, along with Vietnamese, Indian, Turkish, and Chilean places — supplementing the area’s favorite pubs, bistros, and Italian restaurants.