docs(obstacle_cruise_planner): add supplemental figures

[mitukou1109]

Description

This PR adds following images:

• Ego behavior determination flowchart
  
• Cruise planning block diagram
  

How was this PR tested?

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

None.

[github-actions]

Thank you for contributing to the Autoware project!

🚧 If your pull request is in progress, switch it to draft mode.

Please ensure:

• You've checked our contribution guidelines.
• Your PR follows our pull request guidelines.
• All required CI checks pass before marking the PR ready for review.

[github-actions]

Documentation URL: https://autowarefoundation.github.io/autoware.universe/pr-9154/
Modified URLs:

• https://autowarefoundation.github.io/autoware.universe/pr-9154/planning/autoware_obstacle_cruise_planner/

[yuki-takagi-66]

LGTM Thank you

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 28.64%. Comparing base (3e0d3c7) to head (3aa5e64).
Report is 429 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9154      +/-   ##
==========================================
- Coverage   28.64%   28.64%   -0.01%     
==========================================
  Files        1307     1308       +1     
  Lines      101201   101223      +22     
  Branches    39343    39346       +3     
==========================================
+ Hits        28990    28993       +3     
- Misses      69403    69423      +20     
+ Partials     2808     2807       -1     

Flag	Coverage Δ		*Carryforward flag
differential	12.95% <ø> (?)
total	28.64% <ø> (ø)		Carriedforward from 3e0d3c7

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

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