feat(behavior_velocity_planner): replace first_stop_path_point_index

[yhisaki]

Description

Previously, we stored the first stopping point on the path in the variable SceneModuleInterface::first_stop_path_point_index_. However, we plan to replace this with a class that handles paths continuously in the future by using autoware_trajectory. In this case, the current method of directly handling path point indices should be replaced with a method that handles distances from the path's starting point.
In this PR, instead of using the variable SceneModuleInterface::first_stop_path_point_index_, we now manage the first_stop_path_point using the variable SceneModuleInterface::first_stop_path_point_distance_. SceneModuleInterface::first_stop_path_point_distance_ represents the distance from the path's starting point.

Related links

How was this PR tested?

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

None.

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[codecov]

Codecov Report

Attention: Patch coverage is 51.72414% with 14 lines in your changes missing coverage. Please review.

Project coverage is 29.20%. Comparing base (8652963) to head (86bb47c).
Report is 22 commits behind head on main.

Files with missing lines	Patch %	Lines
...topping_area_module/src/scene_no_stopping_area.cpp	0.00%	6 Missing ⚠️
...havior_velocity_traffic_light_module/src/scene.cpp	0.00%	3 Missing ⚠️
...avior_velocity_detection_area_module/src/scene.cpp	60.00%	1 Missing and 1 partial ⚠️
...e_behavior_velocity_stop_line_module/src/scene.cpp	0.00%	2 Missing ⚠️
...vior_velocity_traffic_light_module/src/manager.cpp	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9296      +/-   ##
==========================================
- Coverage   29.21%   29.20%   -0.02%     
==========================================
  Files        1335     1339       +4     
  Lines      102960   103010      +50     
  Branches    39950    39958       +8     
==========================================
  Hits        30080    30080              
- Misses      70010    70059      +49     
- Partials     2870     2871       +1     

Flag	Coverage Δ		*Carryforward flag
differential	21.76% <51.72%> (?)
total	29.20% <ø> (-0.01%)	⬇️	Carriedforward from 7007bc6

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[satoshi-ota]

Looks good.