Previously we only display the warning when it's a new key format
`<object>.<property>`, we should display all cases to help users
understand where the new key is moved to
x-ref: https://x.com/huozhi/status/1789335665252921381
We have dropped `experimental.appDir` option, to share the insights that can be removed, add a warning `"App router is enabled by default now, <experimental.appDir> option can be safely removed.'" `
There're few places calling `loadConfig` to access nextjs config for different purpose, and every of them will do validation of next config scheme and could log the warnings potentially to cause duplicated warnings. To address that issue this PR limit the places when should the warnings be logged in certain places, mainly the `next` command entry. Refactor the API here to make it more explicit
Previous logging redeisgn also might trigger duplicated compilation, for instance you compiled page A but then editing another component it might still displaying page A is recompiled. Now we always display `"Compiled .."` message when there's a recompilation but avoid the unnecessary ones such as initial edge compilor ready but there's no modules inside. Then when it recompiles or recovers from error nextjs server will tell "Compiled .." instead of the specific page which might be not related.
Also refactors a minor issue: When `silent` option is set to `true`, auto recorrect next config option from `loadConfig` API like `traillingSlash` is not working
Closes NEXT-1610
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
