chore(intersection): add const to member functions, replace enum with class tag for occlusion

[soblin]

Description

added const to member functions for readability

Tests performed

https://evaluation.tier4.jp/evaluation/reports/a40b1c77-0f2a-5017-95e8-f397bf4c3f25?project_id=prd_jt

Effects on system behavior

Not applicable.

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[codecov]

Codecov Report

Attention: 25 lines in your changes are missing coverage. Please review.

Comparison is base (0b90a97) 14.90% compared to head (01ea64a) 14.90%.
Report is 6 commits behind head on main.

Files	Patch %	Lines
...ity_intersection_module/src/scene_intersection.cpp	0.00%	16 Missing ⚠️
...ection_module/src/scene_intersection_occlusion.cpp	0.00%	5 Missing ⚠️
...ection_module/src/scene_intersection_collision.cpp	0.00%	2 Missing ⚠️
...elocity_intersection_module/src/object_manager.cpp	0.00%	1 Missing ⚠️
...ity_intersection_module/src/scene_intersection.hpp	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6299      +/-   ##
==========================================
- Coverage   14.90%   14.90%   -0.01%     
==========================================
  Files        1817     1817              
  Lines      125466   125471       +5     
  Branches    37706    37707       +1     
==========================================
  Hits        18699    18699              
- Misses      85751    85756       +5     
  Partials    21016    21016              

Flag	Coverage Δ		*Carryforward flag
differential	4.62% <0.00%> (?)
total	14.90% <ø> (+<0.01%)	⬆️	Carriedforward from 0b90a97

*This pull request uses carry forward flags. Click here to find out more.

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