up: handle various attach use cases better

[milas]

What I did
By default, compose up attaches to all services (i.e. shows log output from every associated container). If a service is specified, e.g. compose up foo, then only foo's logs are tailed. The --attach-dependencies flag can also be used, so that if foo depended upon bar, then bar's logs would also be followed. It's also possible to use --no-attach to filter out one or more services explicitly, e.g. compose up --no-attach=noisy would launch all services, including noisy, and would show log output from every service except noisy. Lastly, it's possible to use up --attach to explicitly restrict to a subset of services (or their dependencies).

How these flags interact with each other is also worth thinking through.

There were a few different connected issues here, but the primary issue was that running compose up foo was always attaching dependencies regardless of --attach-dependencies.

The filtering logic here has been updated so that it behaves predictably both when launching all services (compose up) or a subset (compose up foo) as well as various flag combinations on top of those.

Notably, this required making some changes to how it watches containers. The logic here between attaching for logs and monitoring for lifecycle changes is
tightly coupled, so some changes were needed to ensure that the full set of services being up'd are watched and the subset that should have logs shown are attached. (This does mean faking the attach with an event but not actually doing it.)

While handling that, I adjusted the context lifetimes here, which improves error handling that gets shown to the user and should help avoid potential leaks by getting rid of a context.Background().

Related issue
Fixes:

• Detach mode prints full output #10909

(not mandatory) A picture of a cute animal, if possible in relation to what you did

[codecov]

Codecov Report

Patch coverage: 68.57% and project coverage change: +0.08% 🎉

Comparison is base (792afb8) 58.71% compared to head (6590b94) 58.80%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10910      +/-   ##
==========================================
+ Coverage   58.71%   58.80%   +0.08%     
==========================================
  Files         120      120              
  Lines       10477    10540      +63     
==========================================
+ Hits         6152     6198      +46     
- Misses       3722     3738      +16     
- Partials      603      604       +1     

Files Changed	Coverage Δ
pkg/compose/start.go	62.34% <48.64%> (-3.09%)	⬇️
cmd/compose/up.go	67.06% <65.00%> (-1.46%)	⬇️
pkg/utils/set.go	68.51% <100.00%> (+33.90%)	⬆️

... and 3 files with indirect coverage changes

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