documentation for `strong-mode` rules

[DetachHead]

Describe the issue
there seems to be no documentatioin for the analyzer.strong-mode options. though the implicit-casts option is mentioned briefly here, i can't seem to find any documentation for the other options.

i think there are 2 more (implicit-dynamic and declaration-casts)

[parlough]

Is there a reason you want to use the strong-mode options over the newer strict language modes as described in Enabling stricter type checks? They cover all of the previously covered situations and more.

We are still documenting implicit-casts there as the equivalent strict-casts mode was recently implemented in Dart 2.16. The plan is to remove the documentation around that in the future as well.

I think the actionable work here is probably to introduce diagnostics that the strong-mode options are deprecated and point towards to the new language modes.

[DetachHead]

is there a analyzer.language equivalent to analyzer.strong-mode.implicit-dynamic?

[parlough]

I believe it is strict-inference that should cover similar situations and more and strict-raw-types covers cases related to missing type arguments resulting in dynamic bounds.

If you find any cases that are missing or could be caught but aren't, opening an SDK issue would be great :)

[DetachHead]

raised #48651

[scheglov]

@srawlins

[srawlins]

The strong-mode rules are soft deprecated; soon to be for reals deprecated, so we will not be writing documentation for them.

[parlough]

I think this can be closed since the strong-mode rules were deprecated/removed in Dart 3 and the strict language modes are documented in https://dart.dev/guides/language/analysis-options#enabling-additional-type-checks :)

Edit: Never mind, looks like the removal was reverted in 94f20d7. Either way, we likely shouldn't document these deprecated modes.