stateless tipg: remove `collection_catalog`

[vincentsarago]

Since the start of tifeature/timvt/tipg, we designed the application with having a list of the available collections/layers stored in the application State: https://github.com/developmentseed/tipg/blob/489f0243b0b4f0d46d12f06a1baf0bccc1d4232a/tipg/db.py#L83

This gave some advantages:

• cost of running the collection listing is only paid once (at startup)
• we know what are the available collection so we can raise useful error if the user input collection is not in the list https://github.com/developmentseed/tipg/blob/489f0243b0b4f0d46d12f06a1baf0bccc1d4232a/tipg/dependencies.py#L40-L43
• cheap collection filtering https://github.com/developmentseed/tipg/blob/main/tipg/factory.py#L439-L458

The collection_catalog is created at application startup https://github.com/developmentseed/tipg/blob/489f0243b0b4f0d46d12f06a1baf0bccc1d4232a/tipg/main.py#L65-L80 because we assumed it's a pretty costly process.

The problem then (as explained in https://github.com/developmentseed/eoAPI/pull/55#issuecomment-1471006644) is when you have changed in the DB (e.g new table) it won't show up in the application because the catalog is now updated.

Proposal

• remove collection_catalog
• create a clean SQL function which will list the collections
• the function should accept id (to return only one collection), limit, offset, spatial_filter and temporal_filter

cc @bitner

[bitner]

We will also need to take into account merging in the overrides that can come from environment variables.

I will note, that we can use the existing function right now to filter by collection by setting tables= and functions=.