fix: app slow loading workflows

[doc-han]

Description

This PR optimises the db query on the workflows list page. instead of doing 5 queries per workflow on the page. we collect the workflow ids and do a single batch query per group.

Closes #3675
Closes #2426

Validation steps

Non technical

1. How fast does opening a project now feel?

Technical

1. Check the number of queries being fired(in terminal) whenever you try to open a project to view the list of workflows

Additional notes for the reviewer

1. (Is there anything else the reviewer should know or look out for?)

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.48%. Comparing base (734287a) to head (3f997d4).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4478      +/-   ##
==========================================
+ Coverage   89.43%   89.48%   +0.05%     
==========================================
  Files         425      425              
  Lines       20253    20303      +50     
==========================================
+ Hits        18113    18169      +56     
+ Misses       2140     2134       -6     

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[midigofrank]

Nicely done @doc-han . This will definitely improve the loading times. Can we do a follow up issue that uses async_assigns to load the stats? https://hexdocs.pm/phoenix_live_view/Phoenix.LiveView.html#module-async-assigns

---EDIT---

I have created it here: #4489