This is a mostly-automated fixup using Comby (https://comby.dev) to remove 
lexically-obvious redundant error checks. No functional changes are intended.

To reproduce the core change:

    # Collapse redundant error check conditionals
    % comby -in-place 'if err != nil {
       return err
    }
    return nil' 'return err' .go

    # Fold out unnecessary error temporaries
    % comby -in-place ':[spc~^\s*]err :[~:?]= :[any]
       return err' ':[spc]return :[any]' .go

Fixes #6479 and related cases.

Follow up from PR: #6740

This changes adds an `MempoolError` field to the `ResponseCheckTx`. This will allow clients to understand that their transaction was rejected from the mempool despite passing the ABCI check. 

This change also updates the code to make use of early returns to prevent highly nested code blocks. Namely, it returns when the type assertion fails at the beginning of the method, instead of wrapping the entire method in a large if statement. This has a somewhat large effect on the diff as rendered by github.

addresses: #3546

## Description

Internalize some libs. This reduces the amount ot public API tendermint is supporting. The moved libraries are mainly ones that are used within Tendermint-core.

## Description

Add sr25519 as a validator key option. We support the crypto in tendermint and added batch verification recently.

## Description

- removes blocktimeiota 
- merges block params in abci and core state
- spec change: https://github.com/tendermint/spec/pull/248


Closes: #5939

## Description

- bump gogoproto (1.3.2)
- regenerate proto files

Closes: #XXX

Fixes #5866. Inbound traffic monitoring (and by extension inbound rate limiting) was inadvertently removed in 660e72a.

Migrate ABCI to use protoio (uint64 length delimitation) instead of specific int64 length delimiters.

Closes: #5783

`abci.Client`:

- Sync and Async methods now accept a context for cancellation
    * grpc client uses context to cancel both Sync and Async requests
    * local client ignores context parameter
    * socket client uses context to cancel Sync requests and to drop Async requests before sending them if context was cancelled prior to that

- Async methods return an error
    * socket client returns an error immediately if queue is full for Async requests
    * local client always returns nil error
    * grpc client returns an error if context was cancelled before we got response or the receiving queue had a space for response (do not confuse with the sending queue from the socket client)

- specify clients semantics in [doc.go](https://raw.githubusercontent.com/tendermint/tendermint/27112fffa62276bc016d56741f686f0f77931748/abci/client/doc.go)

`mempool.TxInfo`

- add optional `Context` to `TxInfo`, which can be used to cancel `CheckTx` request

Closes #5190

## Description

- add `AbciVersion` RequestInfo

Closes: #2804

Remove Response/Request SetOption from ABCI.

Co-authored-by: Anton Kaliaev <anton.kalyaev@gmail.com>

Adds a genesis parameter `initial_height` which specifies the initial block height, as well as ABCI `RequestInitChain.InitialHeight` to pass it to the ABCI application, and `State.InitialHeight` to keep track of the initial height throughout the code. Fixes #2543, based on [RFC-002](https://github.com/tendermint/spec/pull/119). Spec changes in https://github.com/tendermint/spec/pull/135.

Fixes #5177.

adds blockstore interface to evidence and adds fix to byzantine test

## Description

THis pr adds `json_name` to replace proto generated json tags. 

Closes: #5111

Closes #5125

- the sequence does not start with 1
- RequestDeliverTx has out-of-order field number

Closes #5115

Reorganizes the Protobuf schemas. It is mostly bikeshedding, so if something is contentious or causes a lot of extra work then I'm fine with reverting. Some Protobuf and Go import paths will change.

* Move `abci/types/types.proto` to `abci/types.proto`.

* Move `crypto/keys/types.proto` and `crypto/merkle/types.proto` to `crypto/keys.proto` and `crypto/proof.proto`.

* Drop the use of `msgs` in filenames, as "message" is a very overloaded term (all Protobuf types are messages, and we also have `message Message`). Use `types.proto` as a catch-all, and otherwise name files by conceptual grouping instead of message kind.

Fixes some minor issues with Protobuf enums, not likely to break anything.

Branched off of #5096, rebase to `master` before merging.

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Refs #4581

Co-authored-by: JamesRay <66258875@qq.com>

making it possible to change app version via EndBlock

## Description

have the defined abci proto types follow the same directory structure as in abci folder.

Closes: #XXX

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

## Description

This PR moves all proto files under one dir (`/proto`). The script to generate adding functionality to copy the files that still need to be in the same place. (abci & rpc)

renames every proto package from `tendermint.proto.<pkg_name>` to `tendermint.<pkg_name>`

Removes unneeded types in privval proto directory

Closes: #XXX

* test-vectors for backwards compatibility:

 - copy & paste test-vectors from v0.33.5 to ensure
 backwards compatibility for vote's SignBytes

* WIP: everything besides time seems to match :-/

* almost

* Found the culprit: field nums weren't consecutive ints ...

* fix order of partset header too

* this last votes-related test can easily be fixed

* some minor changes and fix last failing test

* move proto types back to stdtime, fix various linting

* use libs/protoio

* remvoe commented code

* add comments

* fix tests

* uncomment testscases

* dont ignore error panic

* fix signable test

* fix happy path testing

* fix comment

Co-authored-by: Marko Baricevic <marbar3778@yahoo.com>

## Description

This PR removes simple prefix from all types in the crypto/merkle directory.

The two proto types `Proof` & `ProofOp` have been moved to the `proto/crypto/merkle` directory.

proto messge `Proof` was renamed to `ProofOps` and `SimpleProof` message to `Proof`. 

Closes: #2755

## Description

In https://github.com/tendermint/tendermint/pull/4466 a new type was created (EventAttribute) that replaced KV.Pair. This made the type Pair deadcode, this pr removes that type.

I don't think a changelog entry is needed since it is not being used anymore. But will add a section to the upgrading.md to let users know that it was replaced

Closes: #XXX

## Description

remove test files for proto stubs

Closes: #XXX

gogoproto is here to stay.

## Description

regenerate proto stubs

I do find max_num to be vague. possibly renaming to max_entries or max_evidence_entries may be more descriptive?

Closes: #XXX

The number of evidence that can be committed in a single block is capped by a new evidence parameter called MaxNum

Fix some linter issues to conform with the Protobuf style guide.

The state sync enum changes are ok to break since it's not released yet. Personally I find the uppercase kind of ugly, but that's what the guide says. Couldn't find a way to generate camel case in Go, short of specifying custom names for each and every enum variant.

Another option would be to simply disable the enum case lint.

## Description
- enable nolintlint
- disable linting on tests

Closes: #XXX

Adds the ABCI interface for [state sync](https://github.com/tendermint/tendermint/issues/828) as outlined in [ADR-053](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-053-state-sync-prototype.md), and bumps ABCIVersion to `0.17.0`.

The interface adds a new ABCI connection which Tendermint can use to query and load snapshots from the app (for serving snapshots to other nodes), and to offer and apply snapshots to the app (for state syncing a local node from peers).

Split out from the original PR in #4645, state sync reactor will be submitted as a separate PR. The interface is implemented by the Cosmos SDK in https://github.com/cosmos/cosmos-sdk/pull/5803.

The PR added a new field `index` to event attribute, that will cause indexer service to index the event if set to true.