refactor(radar_fusion_to_detected_object)!: 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

All modified and coverable lines are covered by tests ✅

Project coverage is 0.00%. Comparing base (507e3f4) to head (d073e99).
Report is 145 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #7650       +/-   ##
==========================================
- Coverage   14.84%   0.00%   -14.85%     
==========================================
  Files        1999      34     -1965     
  Lines      139163    1969   -137194     
  Branches    43716     101    -43615     
==========================================
- Hits        20661       0    -20661     
+ Misses      95731    1969    -93762     
+ Partials    22771       0    -22771     

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

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[scepter914]

LGTM
(Note: without checking acting, after integrating with other PRs and checking acting this PR can be merged)