Move stats in a `metadata.stats` objects

[antoine-de]

And add more counts:

• trips_with_trip_headsign_count: usize,
• lines_with_short_name_count: usize,
• lines_with_long_name_count: usize,
• transfers_count: usize,
• fares_attribute_count: usize,

There is no fare_rules yet, they are not handled by gtfs structures yet

fixes #188 #189 #190 and partially #191 since we need to handle fare_rules

[antoine-de]

I added the fare rules count too as it has been merged in gtfs-structures (in https://github.com/rust-transit/gtfs-structure/pull/157)

By curiosity, do you know if there are producers that have implemented the fares v2 model?

[AntoineAugusti]

Thanks for the changes!

By curiosity, do you know if there are producers that have implemented the fares v2 model?

Not yet 😢 Grand Est / Fluo may be the first in the coming months, they are working with Cityway on it.

[AntoineAugusti]

@antoine-de Can you push the latest commit on the stats branch? To make sure things are fixed 👌

[antoine-de]

done, sorry forgot this

[antoine-de]

nice, can I merge?

[AntoineAugusti]

Yup, looks good.

Should we bump the version? Or in the next PR when removing attributes?

[antoine-de]

since it's a binary and not a library, we have never kept clean version in this, but you're right, maybe we can update the version after removing the fields