176: Expand dev launch with configurable vehicle-spawn + fixed spectator

[MaxJa4]

Description

Adds a node which is started by dev.launch. It spawns a configurable amount of vehicles and either teleports the spectator to the hero once or snaps him to the vehicle continuously. Also, vehicle lane changing of NPCs can be disabled/enabled. Spawned vehicles can be restricted to only cars (4 wheels).
Also, the simulation performance (Spectator window) is significantly faster now, as well as the RVIZ camera output (YMMV).

Fixes #176

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings

[samuelkuehnel]

nice improvements, really helpful for testing. Maybe deacifvate dev launch in docker compose before merge.

[samuelkuehnel]

nice improvements, really helpful for testing. Maybe deacifvate dev launch in docker compose before merge.

[github-actions]

Simulation results

Metric	Value
Avg. driving score	0.011422
Avg. route completion	5.97
Avg. infraction penalty	0.002198
Collisions with pedestrians	0.0
Collisions with vehicles	19.732
Collisions with layout	3.289
Red lights infractions	1.096
Stop sign infractions	0.0
Off-road infractions	0.098
Route deviations	0.0
Route timeouts	1.096
Agent blocked	1.096
Yield emergency vehicles infractions	0.0
Scenario timeouts	3.289
Min speed infractions	0.0