feat(lane_change): ensure LC merging lane stop point is safe

[mkquda]

Description

In case of LC merging lane pattern, the width of the lane at the stop point is not guaranteed to be sufficient for ego vehicle. If LC path is not approved and ego continues up to stop point, ego body can exceed lane boundaries which is unsafe.

Changes

• added function isMergingLane in planner common utils to check for merging lane pattern
• added function getDistanceFromLastFitWidthToEnd in planner common utils to compute distance from last center line point within width threshold to lane end
• refactor function getSignedDistanceFromBoundary in planner common utils
• in case of LC merging lane pattern, subtract computed distance from distance_to_terminal to ensure safe stopping point

How was this PR tested?

tested with psim.

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

When ego is approaching end of merging lane and LC path is not approved, ego should stop at safe point where ego body does not exceed lane boundaries

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 43 lines in your changes missing coverage. Please review.

Project coverage is 23.78%. Comparing base (196b9fa) to head (aacea06).
Report is 5 commits behind head on main.

Files	Patch %	Lines
..._path_lane_change_module/src/utils/calculation.cpp	0.00%	21 Missing ⚠️
...e_behavior_path_planner_common/src/utils/utils.cpp	0.00%	15 Missing ⚠️
...are_behavior_path_lane_change_module/src/scene.cpp	0.00%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8369      +/-   ##
==========================================
- Coverage   23.87%   23.78%   -0.09%     
==========================================
  Files        1380     1389       +9     
  Lines      101867   101755     -112     
  Branches    38802    38622     -180     
==========================================
- Hits        24320    24205     -115     
+ Misses      75123    75093      -30     
- Partials     2424     2457      +33     

Flag	Coverage Δ		*Carryforward flag
differential	15.03% <0.00%> (?)
total	23.88% <ø> (+0.01%)	⬆️	Carriedforward from 91a0af3

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

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[zulfaqar-azmi-t4]

LGTM. Thank you for fixing this issue!

[xmfcx]

Once this was merged, we started having test errors in the CI:
https://github.com/autowarefoundation/autoware.universe/actions/runs/10416334778

1 package had test failures: autoware_freespace_planning_algorithms

https://github.com/autowarefoundation/autoware.universe/actions/runs/10416334778/job/28848368965#step:16:17822

@mkquda could you look into it?

List: https://github.com/autowarefoundation/autoware.universe/actions/workflows/build-and-test.yaml?query=branch%3Amain

[xmfcx]

This ci failed last week too:
https://github.com/autowarefoundation/autoware.universe/actions/runs/10314646396