fix: batch observed function eval in plotting, bug fixes

[AayushSabharwal]

Checklist

• Appropriate tests were added
• Any code changes were done in a way that does not break public API
• All documentation related to code changes were updated
• The new code follows the
  contributor guidelines, in particular the SciML Style Guide and
  COLPRAC.
• Any new documentation only uses public API

Additional context

Add any other context about the problem here.

[AayushSabharwal]

Requires SciML/RecursiveArrayTools.jl#369 and SciML/SymbolicIndexingInterface.jl#70

[codecov]

Codecov Report

Attention: Patch coverage is 94.44444% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 41.00%. Comparing base (9e92fc6) to head (668f3f7).
Report is 4 commits behind head on master.

Files	Patch %	Lines
src/solutions/ode_solutions.jl	83.33%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #680      +/-   ##
==========================================
+ Coverage   31.74%   41.00%   +9.25%     
==========================================
  Files          55       55              
  Lines        4505     4529      +24     
==========================================
+ Hits         1430     1857     +427     
+ Misses       3075     2672     -403     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[AayushSabharwal]

Requires SciML/SymbolicIndexingInterface.jl#72