feat: add traffic rules to enable driving for areas

[emmeyteja]

Description

• Enables Lanelet2 routing / mission planning to consider paths that traverse lanelet → Area → lanelet by extending traffic rules so Areas can be treated as drivable where appropriate.
• Adds RViz visualization for Lanelet2 area layer: filled polygon + outline markers (namespaces such as lanelet_routing_area / lanelet_routing_area_outline) so multipolygon Areas are easy to see on the map (14f99356).

How was this PR tested?

• colcon build / colcon test for autoware_lanelet2_extension (and packages that depend on it).
• Loaded a Lanelet2 map that includes Area relations and confirmed shortest path including areas is accepted when used together with matching autoware_core / route_handler changes (if this PR is paired with those).
• RViz: subscribed to lanelet map markers and confirmed area fill + outline render as expected.

Notes for reviewers

• Visualization changes are largely in visualization.cpp (e.g. areaOuterToPolygon3d, laneletAreasAsMarkerArray); traffic-rule changes should be reviewed for consistency with Lanelet2 RoutingGraph::shortestPathIncludingAreas and existing rule sets.

Related Links

Related PRs

• autoware_core PR
• autoware_universe PR

Issues

• TierIV Internal Issue Link

Design Dcouments

• Tier IV Internal Design Document: Area Visualization
• Tier IV Internal Design Document: Route Serach through Areas

Effects on system behavior

• Routing: With a compatible route_handler / map, routes may include Area segments instead of failing when the only feasible connection is lanelet–area–lanelet.
• Visualization: Maps with an area layer show filled + outlined area polygons in RViz (behavior for operators; default driving policy still depends on traffic rules + planner).

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[codecov]

Codecov Report

❌ Patch coverage is 35.63218% with 56 lines in your changes missing coverage. Please review.
✅ Project coverage is 19.11%. Comparing base (5a32788) to head (887a2d2).
⚠️ Report is 51 commits behind head on main.

Files with missing lines	Patch %	Lines
autoware_lanelet2_extension/lib/visualization.cpp	0.00%	32 Missing and 18 partials ⚠️
...lanelet2_extension/test/src/test_route_checker.cpp	87.09%	0 Missing and 4 partials ⚠️
...extension/traffic_rules/autoware_traffic_rules.hpp	0.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #104      +/-   ##
==========================================
+ Coverage   16.31%   19.11%   +2.79%     
==========================================
  Files          42       44       +2     
  Lines        3089     3594     +505     
  Branches     1397     2040     +643     
==========================================
+ Hits          504      687     +183     
+ Misses       2490     1904     -586     
- Partials       95     1003     +908     

Flag	Coverage Δ
differential	18.94% <35.63%> (+2.20%)	⬆️
total	?

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[emmeyteja]

@mitsudome-r @soblin Could you please review this PR?

[mitsudome-r]

Also, please make sure to add tests for the functions that you add.

[emmeyteja]

@mitsudome-r I added a boolean argument "allow_area" and added tests. Please confirm, if it looks good, I will enable squash-merge.