☂ [Routing samples] Simplify routing and navigation samples

[ericwindmill]

Currently routing is a core feature of two samples: navigation_and_routing and deeplink-store-example. Those two should be simplified into three quickstarts:

• navigation/go_router
• navigation/navigator2
• navigation/deeplinking

• retire deeplink-store-example
  • [deeplink-store-example] deprecate #2516
• simplify navigation_and_routing into navigation/go_router
  • [navigation_and_routing] Simplify into quickstart #2515
• create a simple deeplinking quickstart
  • [deeplink quickstart] Create a deeplinking quickstart #2517
• create a simple navigator2 quickstart
  • [navigator2 quickstart] Create a navigator2 quickstart #2518