feat!: Upgrade to DCM 1.19.1

[witwash]

Summary

• upgraded to DCM 1.19.1

  New rules:

• avoid-incorrect-image-opacity

Rules left disabled:

• handle-throwing-invocations - is focused around dart-code-metrics-annotations package which we don't use
• prefer-correct-throws - again, focused around the dart-code-metrics-annotations package
• prefer-extracting-function-callbacks - is a good idea, we could enable it (with a limit of something like 5 lines) but it is flagging a bunch of tests.

Testing steps

None

Follow-up issues

None

Check during review

• Verify against Jira issue.
• Is the PR over 300 additions? Consider rejecting it with advice to split it. Is it over 500 additions? It should definitely be rejected.
• Unused code removed.
• Build passing.
• Is it a bug fix? Check that it is covered by a proper test (unit or integration).

[ookami-kb]

handle-throwing-invocations - is focused around dart-code-metrics-annotations package which we don't use prefer-correct-throws - again, focused around the dart-code-metrics-annotations package

@MewsSystems/tech-mo FYI, I plan to migrate to it (I was actively asking for these rules), but it can take some time and should be done gradually. I think, we will enable them locally first for some packages, and later turn them on in mews-pedantic.

[ookami-kb]

prefer-extracting-function-callbacks - is a good idea, we could enable it (with a limit of something like 5 lines) but it is flagging a bunch of tests.

I'm not a fan of rules like "do smth after function is N lines of code". In the majority of cases, it should rather be based on the meaning rather than its size.