In the Action Editor and Dopesheet, Action/Slot summaries erroneously showed
keys that were hidden in their sub-channels.
The root cause was that the functions for building Action/Slot summary key
lists, `action_to_keylist()` and `action_slot_to_keylist()`, weren't doing
animation filtering *at all*, instead just looping over all f-curves.
This PR fixes the bug by replacing `action_slot_to_keylist()` with a new
`action_slot_summary_to_keylist()` function, which calls into the animation
filtering code to determine which f-curves to include in their key list, and
also using it in place of `action_to_keylist()` at the relevant call sites.
Additionally, properly filtering the channels for the summaries requires both a
`bAnimContext` and the ID that's being animated, so this PR threads those
through to `action_slot_summary_to_keylist()`.
Note that `action_to_keylist()` is still used in some places that actually
*want* an unfiltered list of keys. Those call sites have been left as-is, and
`action_to_keylist()` remains for that purpose.
Pull Request: https://projects.blender.org/blender/blender/pulls/134922
ca980dc4f9