Update tutorial content; move selector group chat and swarm outside of tutorial.

[ekzhu]

1. Improve tutorial content:

• Remove UserProxyAgent subsection in Agents, as its content has been covered by Human-in-the-Loop section that follows.
• Add note to remind users when to move from single agent to a team
• Add note about run and run_stream methods for agents

2. Move selector group chat and swarm out of tutorial to make the tutorial more condensed and focuses on introductory concepts.

3. Add redirect for the moved pages, use sphinxext-rediraffe, updated uv.lock

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.12%. Comparing base (5b9be79) to head (4b8386c).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4915   +/-   ##
=======================================
  Coverage   68.12%   68.12%           
=======================================
  Files         161      161           
  Lines       10179    10179           
=======================================
  Hits         6934     6934           
  Misses       3245     3245           

Flag	Coverage Δ
unittests	68.12% <ø> (ø)

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