refactor(radar_object_tracker)!: fix namespace and directory structure

[technolojin]

Description

This PR puts headers in the autoware namespace.
Part of: autowarefoundation/autoware#4569

Additional works

1. Align directory structure to follow the coding guidelines.
2. Clean unused dependencies LIST

Tests performed

Not applicable.

Effects on system behavior

Not applicable.

Interface changes

Not applicable.

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 55 lines in your changes missing coverage. Please review.

Project coverage is 1.22%. Comparing base (507e3f4) to head (23dc7fa).
Report is 166 commits behind head on main.

Files	Patch %	Lines
...racker/src/tracker/model/linear_motion_tracker.cpp	0.00%	31 Missing ⚠️
...racker/model/constant_turn_rate_motion_tracker.cpp	0.00%	22 Missing ⚠️
...r_object_tracker/src/radar_object_tracker_node.cpp	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #7658       +/-   ##
==========================================
- Coverage   14.84%   1.22%   -13.63%     
==========================================
  Files        1999      77     -1922     
  Lines      139163    4405   -134758     
  Branches    43716     407    -43309     
==========================================
- Hits        20661      54    -20607     
+ Misses      95731    4330    -91401     
+ Partials    22771      21    -22750     

Flag	Coverage Δ
differential	1.22% <0.00%> (?)
total	?

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[YoshiRi]

LGTM