Wire counter module into app and update tutorials

[evanorti]

Add full counter module wiring to app.go and rewrite tutorial docs for clarity. app.go: add counter imports, CounterKeeper field, store key, instantiate CounterKeeper (now accepting BankKeeper), register counter module with ModuleManager, and include counter in genesis/export and begin/end blocker orders. Docs: substantially rewrite quickstart, build-a-module, counter walkthrough, and run-and-test tutorials — improve step ordering, clarify commands and expected outputs, expand explanations for params, fee collection, module accounts, telemetry, AutoCLI, simulation, and testing, and update many code examples and links.