Uniform pallet warnings

[ggwpez]

Cleaning up the code a bit by using proc-macro-warning and emitting a warning when using a hard-coded weight on a non-dev-mode pallet (#13774).
In cases where dev mode is not possible and you explicitly want to ignore this warning; wrap it in curly brackets like {1}.

This enforces consistent formatting and grammar across different warnings for enhanced developer experience.

warning: use of deprecated constant `pallet::warnings::ImplicitCallIndex::_w`: 
                 It is deprecated to use implicit call indices.
                 Please instead ensure that all calls have the `pallet::call_index` attribute or that the `dev-mode` of the pallet is enabled.
         
                 For more info see:
                     <https://github.com/paritytech/substrate/pull/12891>
                     <https://github.com/paritytech/substrate/pull/11381>
    --> frame/nomination-pools/src/lib.rs:2621:10
     |
2621 |         pub fn claim_commission(origin: OriginFor<T>, pool_id: PoolId) -> DispatchResult {
     |                ^^^^^^^^^^^^^^^^
     |

and

warning: use of deprecated constant `pallet::warnings::ConstantWeight::_w`: 
                 It is deprecated to use hard-coded constant as call weight.
                 Please instead benchmark all calls or put the pallet into `dev` mode.
         
                 For more info see:
                     <https://github.com/paritytech/substrate/pull/13798>
    --> frame/nomination-pools/src/lib.rs:2620:20
     |
2620 |         #[pallet::weight(0)]
     |                          

TODO:

• Update and add UI tests

We could also think about a registry of known warnings / errors and have shortened links to them like parity.link/frame-err-123 to explain how to resolve them.

[bkchr]

Nice!

[ggwpez]

bot rebase

[paritytech-processbot]

Rebased

[ggwpez]

Note: Some test-only pallets cannot be put in dev mode, since they access the storage info.
But we could add custom lint attributes to suppress certain warnings, similar to how clippy works.

[sam0x17]

This is great love that you released this feature as a crate as I'd like to use it for some of my things ^_^

[jsidorenko]

Should the places with the #[pallet::weight(0)] inside the docs text also get changed? E.g. here: https://github.com/paritytech/substrate/blob/master/frame/timestamp/src/lib.rs#L83

[ggwpez]

Should the places with the #[pallet::weight(0)] inside the docs text also get changed? E.g. here:

I just tried that locally, and those examples actually compile and have no proper WeightInfo.
So having a warning here for anyone that copy&pastes it is good I think.

[ggwpez]

bot merge

[Polkadot-Forum]

This pull request has been mentioned on Polkadot Forum. There might be relevant details there:

https://forum.polkadot.network/t/april-updates-for-substrate-and-polkadot-devs/2764/1