refactor(diffusion_planner): move postprocessing logic from node to core

[SakodaShintaro]

Description

Move trajectory, candidate trajectories, predicted objects and turn indicator creation from publish_predictions in the node into DiffusionPlannerCore::create_planner_output, which returns a PlannerOutput struct containing all output messages. This makes the core logic testable independently of the ROS node. The node's on_timer now only handles publishing.

How was this PR tested?

• planning simulator
• logging_simulator

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

None.

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[Copilot]

Pull request overview

This PR refactors autoware_diffusion_planner to move postprocessing and message construction out of the ROS node and into DiffusionPlannerCore, enabling core logic to be tested independently from ROS publishing.

Changes:

• Removed prediction postprocessing and output message assembly from DiffusionPlanner node timer callback.
• Added DiffusionPlannerCore::create_planner_output() returning a PlannerOutput bundle (trajectory, candidate trajectories, predicted objects, turn indicator command).
• Moved turn-indicator management state into the core and updated parameter handling accordingly.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 6 comments.

File	Description
planning/autoware_diffusion_planner/src/diffusion_planner_node.cpp	Simplifies on_timer() to call core output builder and publish results.
planning/autoware_diffusion_planner/src/diffusion_planner_core.cpp	Introduces create_planner_output() and migrates turn-indicator logic into core.
planning/autoware_diffusion_planner/include/autoware/diffusion_planner/diffusion_planner_node.hpp	Removes node-side postprocessing API/member references (partially; doc cleanup needed).
planning/autoware_diffusion_planner/include/autoware/diffusion_planner/diffusion_planner_core.hpp	Adds PlannerOutput struct and declares create_planner_output().

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 49 lines in your changes missing coverage. Please review.
✅ Project coverage is 18.17%. Comparing base (a2ee3ef) to head (18833a7).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
...e_diffusion_planner/src/diffusion_planner_core.cpp	0.00%	37 Missing ⚠️
...e_diffusion_planner/src/diffusion_planner_node.cpp	0.00%	12 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #12162      +/-   ##
==========================================
+ Coverage   18.12%   18.17%   +0.05%     
==========================================
  Files        1842     1844       +2     
  Lines      126651   126834     +183     
  Branches    44419    44429      +10     
==========================================
+ Hits        22950    23048      +98     
- Misses      84582    84777     +195     
+ Partials    19119    19009     -110     

Flag	Coverage Δ		*Carryforward flag
daily	20.61% <ø> (ø)		Carriedforward from 091d8b5
daily-cuda	18.14% <ø> (+<0.01%)	⬆️	Carriedforward from 091d8b5
differential-cuda	13.67% <0.00%> (?)
total-cuda	18.12% <ø> (+<0.01%)	⬆️	Carriedforward from 091d8b5

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

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[go-sakayori]

Seems some changes would be made in another PR, so LGTM!