chore: deprecate "plotting" target in favor of "graphics"

[RobPasMue]

As title says -- following discussions we had in the PyAnsys dev meeting, this PR will adapt PyACP to use the graphics target rather than plotting.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.98%. Comparing base (d1f2777) to head (7b3cb51).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #797   +/-   ##
=======================================
  Coverage   94.98%   94.98%           
=======================================
  Files         109      109           
  Lines        5702     5702           
  Branches      323      323           
=======================================
  Hits         5416     5416           
  Misses        285      285           
  Partials        1        1           

Flag	Coverage Δ
direct-launch	91.57% <ø> (ø)
minimum-deps	93.15% <ø> (ø)
python-3.10	94.21% <ø> (ø)
python-3.11	94.14% <ø> (ø)
python-3.12	94.33% <ø> (ø)
server-2024R2	90.77% <ø> (ø)
server-2025R1	94.14% <ø> (ø)
server-2025R2	94.14% <ø> (ø)
server-latest	94.79% <ø> (ø)

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[greschd]

Good stuff, thanks @RobPasMue!

[RobPasMue]

Thanks for the review @greschd -- feel free to merge whenever you think it's appropriate :)