[Core][Eviction policy refactor] Refactor eviction policy to use the same interface as stats collector

[scv119]

Eviction policy should share the same interface as StatsCollector, both of which subscribes to event changes in object store.

Test plan

• unit tests

[scv119]

I think separate the ref_counting might be an overkill here...

[rkooo567]

Are we planning to consolidate spilling & primary copy information to meta store as well? Also, it is supposed to be used by object manager too right?

[bveeramani]

‼️ ACTION REQUIRED ‼️

We've switched our code formatter from YAPF to Black (see #21311).

To prevent issues with merging your code, here's what you'll need to do:

1. Install Black

pip install -I black==21.12b0

2. Format changed files with Black

curl -o format-changed.sh https://gist.githubusercontent.com/bveeramani/42ef0e9e387b755a8a735b084af976f2/raw/7631276790765d555c423b8db2b679fd957b984a/format-changed.sh
chmod +x ./format-changed.sh
./format-changed.sh
rm format-changed.sh

3. Commit your changes.

git add --all
git commit -m "Format Python code with Black"

4. Merge master into your branch.

git pull upstream master

5. Resolve merge conflicts (if necessary).

After running these steps, you'll have the updated format.sh.

[kfstorm]

‼️ ACTION REQUIRED ‼️

We've updated our formatting configuration for C++ code. (see #22725)

This PR includes C++ code change. To prevent issues with merging your code, here's what you'll need to do:

1. Merge the latest changes from upstream/master branch into your branch.

git pull upstream master
git merge upstream/master

2. Resolve merge conflicts (if necessary).

After running these steps, you'll have the updated C++ formatting configuration.

3. Format changed files.

scripts/format.sh

4. Commit your changes.

git add --all
git commit -m "Format C++ code"

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

• If you'd like to keep this open, just leave any comment, and the stale label will be removed.

[stale]

Hi again! The issue will be closed because there has been no more activity in the 14 days since the last message.

Please feel free to reopen or open a new issue if you'd still like it to be addressed.

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