build!: Migrate to pub workspace

[provokateurin]

I'm not sure it will work right away, but let's see 🚀

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 28.88%. Comparing base (5586e9a) to head (cbd2eb0).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
...ckages/nextcloud/lib/src/models/version_check.dart	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2704   +/-   ##
=======================================
  Coverage   28.88%   28.88%           
=======================================
  Files         373      373           
  Lines      138192   138192           
=======================================
  Hits        39923    39923           
  Misses      98269    98269           

Flag	Coverage Δ		*Carryforward flag
account_repository	98.47% <ø> (ø)
cookie_store	99.48% <ø> (ø)
dashboard_app	96.05% <ø> (ø)
dynamite	31.05% <ø> (ø)
dynamite_end_to_end_test	61.75% <ø> (ø)
dynamite_runtime	85.40% <ø> (ø)
interceptor_http_client	97.18% <ø> (ø)
neon_dashboard	96.05% <ø> (ø)		Carriedforward from 5586e9a
neon_framework	59.34% <ø> (ø)
neon_http_client	94.32% <ø> (ø)
neon_notifications	100.00% <ø> (ø)		Carriedforward from 5586e9a
neon_rich_text	100.00% <ø> (ø)		Carriedforward from 5586e9a
neon_storage	94.66% <ø> (ø)
neon_talk	99.45% <ø> (ø)		Carriedforward from 5586e9a
nextcloud	24.36% <0.00%> (ø)
notifications_app	97.36% <ø> (ø)
notifications_push_repository	98.11% <ø> (ø)
sort_box	90.90% <ø> (ø)
talk_app	98.84% <ø> (ø)

*This pull request uses carry forward flags. Click here to find out more.

Files with missing lines	Coverage Δ
...ckages/nextcloud/lib/src/models/version_check.dart	64.70% <0.00%> (ø)

[Leptopoda]

some initial feedback

[Leptopoda]

We should have it as a dev_dependency of the workspace package and just use a global analysis_options.yaml.

Every package may still alter the rule set but this would make our lints the default (also for newly added packages).

[provokateurin]

I didn't think about this, but yes it makes sense. How are we going to handle custom_lint though? We need to disable some of the rules for specific packages?
OTOH this brings up the point of removing custom_lint entirely, given that it mostly causes headaches and hasn't caught so many problems so far.

[provokateurin]

For the tests with downgraded dependencies we probably need test: ^1.25.12: https://github.com/dart-lang/test/blob/master/pkgs/test/CHANGELOG.md#12512
Unfortunately we are currently stuck: #2680