refactor(lane_change): refactor longitudinal acceleration sampling

[mkquda]

Description

when sampling lane change paths, the min & max longitudinal accelerations are computed once using the maximum prepare duration setting. The longitudinal acceleration is then sampled between the computed min & max values, and used to generated prepare phase metrics.

However when ego is approaching terminal, the prepare duration will also be sampled between 0 and max prepare duration, in that case the min & max longitudinal acceleration values computed previously can be invalid for prepare duration lower than max prepare duration, and can result in failure to generate LC path.

Therefore, it is more logical to compute min & max longitudinal accelerations and sample it for each prepare duration separately.

Changes

• Move longitudinal acceleration sampling code to calculation.cpp
• Refactor calc_prepare_phase_metrics to sample lon acceleration for each prepare duration separately
• Remove unused functions

Related links

None.

How was this PR tested?

• PSIM.
• TIER IV Internal Evaluation

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

None.

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[codecov]

Codecov Report

Attention: Patch coverage is 69.13580% with 25 lines in your changes missing coverage. Please review.

Project coverage is 27.85%. Comparing base (06adbc4) to head (14da1cd).
Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
..._path_lane_change_module/src/utils/calculation.cpp	68.57%	14 Missing and 8 partials ⚠️
...are_behavior_path_lane_change_module/src/scene.cpp	72.72%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9091      +/-   ##
==========================================
- Coverage   28.26%   27.85%   -0.41%     
==========================================
  Files        1306     1303       -3     
  Lines      101091    95780    -5311     
  Branches    39243    39015     -228     
==========================================
- Hits        28573    26683    -1890     
+ Misses      69761    66340    -3421     
  Partials     2757     2757              

Flag	Coverage Δ		*Carryforward flag
differential	19.97% <69.13%> (?)
total	27.19% <ø> (-1.07%)	⬇️	Carriedforward from a282428

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