Add section for comparison and logical query operators

[Fashander]

Description

Closes #1314.

Readiness checklist

• I added tests for new functionality or bugfixes.
• I ran task all, and it passed.
• I added/updated comments for both exported and unexported top-level declarations (functions, types, etc).
• I checked comments rendering with task godocs.
• I ensured that the title is good enough for the changelog.
• (for maintainers only) I set Reviewers (@FerretDB/core), Assignee, Labels, Project and project's Sprint fields.
• I marked all done items in this checklist.

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Name	Status	Preview	Updated
ferret-db	✅ Ready (Inspect)	Visit Preview	Dec 20, 2022 at 2:32PM (UTC)

[codecov]

Codecov Report

Merging #1647 (bd4fe77) into main (d8af79b) will increase coverage by 17.83%.
The diff coverage is n/a.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1647       +/-   ##
===========================================
+ Coverage   51.11%   68.94%   +17.83%     
===========================================
  Files         289      289               
  Lines       14119    14119               
===========================================
+ Hits         7217     9735     +2518     
+ Misses       6102     3437     -2665     
- Partials      800      947      +147     

Impacted Files	Coverage Δ
internal/handlers/tigris/tigrisdb/errors.go	32.14% <0.00%> (-10.72%)	⬇️
internal/handlers/tigris/msg_create.go	67.60% <0.00%> (-7.05%)	⬇️
internal/handlers/tigris/tigrisdb/collections.go	61.90% <0.00%> (-4.77%)	⬇️
internal/util/version/version.go	70.58% <0.00%> (-4.42%)	⬇️
integration/helpers.go	85.50% <0.00%> (+0.96%)	⬆️
internal/handlers/pg/pjson/pjson.go	81.66% <0.00%> (+1.66%)	⬆️
internal/clientconn/listener.go	76.47% <0.00%> (+1.76%)	⬆️
internal/types/document_validation.go	100.00% <0.00%> (+2.53%)	⬆️
internal/handlers/pg/pgdb/tables.go	64.70% <0.00%> (+2.94%)	⬆️
internal/handlers/pg/pgdb/query_iterator.go	76.47% <0.00%> (+2.94%)	⬆️
... and 58 more

Flag	Coverage Δ
integration	64.81% <ø> (+24.42%)	⬆️
mongodb	14.35% <ø> (-0.01%)	⬇️
pg	54.02% <ø> (?)
tigris	37.91% <ø> (-0.10%)	⬇️
unit	28.10% <ø> (-0.03%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

[chilagrow]

Thanks for this 💪 some early comments.

[chilagrow]

Just tiny formatting comment. Looking good!

[rumyantseva]

👍 👍 👍

LGTM, one tiny formatting note.