polkadot-omni-node: add GetParachainInfo runtime api

[iulianbarbu]

Description

Closes #7384
Closes #75
Closes #8692
Closes #8739

Integration

Node developers, node operators & runtime developers will not need to generate chain specs that contain a para_id field starting with this PR, but they'll have to implement the cumulus_primitives_core::GetParachainInfo runtime API once they drop the para_id field, so that new nodes versions will be able to query the runtime for the parachain id.

Starting with 2512 the nodes will not support anymore reading the parachain id from chain specs para_id field, so it will be mandatory for runtime to implement the cumulus_primitives_core::GetParachainInfo trait and be upgraded.

Review Notes

This PR is based on prior work here: #7546. It delivers the following:

Deprecated para_id chain spec extension

• nodes like polkadot-omni-node/polkadot-parachain) will still support running chainspecs with para_id extension for a while (until stable2512)
• nodes like test-parachain/parachain-template-node are supporting only runtimes that implement the new runtime API.
• chain-spec-builder will display that para_id is deprecated when calling help, or when using the flag.

Additional cleanup/changes

• fixed & renabled some omni-node/parachain-template-node tests from polkadot-sdk-docs & templates/zombienet, which rely on the newly added runtime API as wellI. Tests based on the para_id chain spec extension are not present anymore, since omni-node will favour taking the para id based on the runtime API if present.

• removed the concept of running minimal with omni-node. I returned to an old idea of a few of us. At this moment we can't support it anymore with omni-node since we'd need to add parachain_info to minimal-template-runtime, which doesn't make much sense.

• most of the parachains runtimes (hope I haven't missed any relevant) that run by using polkadot-parachain/polkadot-omni-node/test-parachain/parachain-template-node should fail to work with the previous nodes (that support them) after stable2512. Probably that will be caught in the CI if I missed them during this PR, but I doubt it.

Reviewers request

• if there are other nodes used to run parachains runtimes, this is a good moment to highlight them so that I can update them if needed in terms of picking up the parachain_id from the runtime.

[cla-bot-2021]

User @Stephenlawrence00, please sign the CLA here.

[skunert]

I thought chain specs produced by stable2509 nodes (I imagine the main node we're discussing here is polkadot-parachain), probably via export-chain-spec, or produced via chain-spec-builder should still work with previous nodes (even if wasm blobs come with an extra API). E.g. 2503 polkadot-omni-node binary loads/finalizes blocks correctly with the dev chain spec of the parachain template runtime, with the GetParachainIdentifier trait (at least under the zombienet-omni-node.toml network).

The extra runtime API is not the problem. But if you export a chain-spec with this new node, the para_id will be missing from it. So if you pass it to an old node, it does not know about our introduced runtime API and will go looking for the para_id in the spec. This is a breaking change. Wo we can either:

1. Keep the para_id in the chain-spec exported by the new node and only internally ignore it if the runtime API is available. This is best compatibility wise.
2. Keep the current state at the cost of chain-spec compatibility between new specs and old nodes. Allows for faster deprecation though. I think its okay to go with this one, but we should try to communicate it clearly in the prdoc.

[iulianbarbu]

But if you export a chain-spec with this new node, the para_id will be missing from it.

Very true, missed this. Will add a note in the prdoc about the fact chain specs generate with export-chain-spec via stable2509 nodes will not be runnable by older nodes' versions.

[iulianbarbu]

/cmd fmt