[WIP] Make Player a rosbag2 component (instead of rosbag2_transport)

[roncapat]

Closes #1736

This is a proposal to address https://github.com/ros2/rosbag2/pull/1510/files#r1484600093.

CC @MichaelOrlov @fujitatomoya

NOTE: I compiled it and the component gets correclty exposed via ros2 component types but I haven't tested it yet.

If it works, I extend it also to Recorder and then it's ready for merge.

[roncapat]

@MichaelOrlov may I ask if you are still interested in this, and if the proposed method is ok for you, so I can apply the same strategy for Recorder??

[MichaelOrlov]

Hi @roncapat, Yes, I am still interested in this PR.
However, it is too long to describe what needs to be changed.
Instead, I did prototyping and made a couple of direct commits to your branch. Please see c00bf42 and 4f6414e

Please review the changes and feel free to add a composable_recorder.{hpp}cpp file in a similar way.

I've tested loading a new composable rosbag2::Plyer in my local setup and can confirm that it is compiles and runs as expected. However, it would be good to add some unit tests.

To test it I ran in one terminal

ros2 run rclcpp_components component_container

in another terminal

ros2 component load /ComponentManager rosbag2 rosbag2::Player -p storage.uri:=/recordings/talker/talker.mcap -p play.loop:=true

After that, you can try to run ros2 component list and ros2 topic echo /topic to make sure that rosbag2::Player composable node is up and running.

I took talker.mcap from the https://github.com/ros2/rosbag2/blob/rolling/rosbag2_py/test/resources/mcap/talker/talker.mcap

[roncapat]

@MichaelOrlov looks nice to me! As soon as I have a bit of time, I will do the same for Recorder class.

[MichaelOrlov]

cc: @emersonknapp

[roncapat]

@MichaelOrlov done, sorry for the delay.

[MichaelOrlov]

@roncapat Thank you for the follow-up.
The latest changes look mostly good to me. I pushed one commit with fixes for the CPPLint warnings.

What we are missing now is a basic integration unit tests to make sure that invoking composable player can be constructed and play messages and composable recorder can be constructed from CLI command and record messages.
In Rosbag2 we have a special package rosbag2_tests for such type of integration tests where almost all required instrumentation already defined.

Could you please write a few integration tests?
You can use test_rosbag2_record_end_to_end.cpp and test_rosbag2_play_end_to_end.cpp as a good reference and example.
Also feel free to use cdr_test bag files from resource folder for playback test.
For recording tests feel free to use RecordFixture class. There are already present instrumentation to handle recorded files from Rosbag2 recorder in the system temp folder.

Also could you please sign your 51d303f commit to pass DCO check on CI?