docs: BROS-351: Add docs for Chat tag

[hlomzik]

• New page in Object tags docs
• Move PDF further for correct order
• Fake Chat tag in tags to auto-generate params (like we do for Text and HyperText)

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 8.78%. Comparing base (2e76824) to head (140f8ba).
⚠️ Report is 9 commits behind head on develop.

❗ There is a different number of reports uploaded between BASE (2e76824) and HEAD (140f8ba). Click for more details.

HEAD has 3 uploads less than BASE

Flag	BASE (2e76824)	HEAD (140f8ba)
pytests	1	0
lsf-e2e	1	0
lsf-integration	1	0

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #8314       +/-   ##
===========================================
- Coverage    66.43%   8.78%   -57.66%     
===========================================
  Files          753     478      -275     
  Lines        55690   32591    -23099     
  Branches      9911    8863     -1048     
===========================================
- Hits         36999    2862    -34137     
- Misses       18688   29726    +11038     
  Partials         3       3               

Flag	Coverage Δ
lsf-e2e	?
lsf-integration	?
lsf-unit	8.78% <ø> (ø)
pytests	?

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