Statement store (#13701)

* WIP Statement store

* Sync with networking changes in master

* WIP statement pallet

* Statement validation

* pallet tests

* Validation queue

* Store maintenance

* Basic statement refactoring + tests + docs

* Store metrics

* Store tests

* Store maintenance test

* cargo fmt

* Build fix

* OCW Api

* Offchain worker

* Enable host functions

* fmt

* Minor tweaks

* Fixed a warning

* Removed tracing

* Manual expiration

* Reworked constraint management

* Updated pallet constraint calculation

* Added small test

* Added remove function to the APIs

* Copy-paste spec into readme

* Comments

* Made the store optional

* Removed network protocol controller

* fmt

* Clippy fixes

* fmt

* fmt

* More clippy fixes

* More clippy fixes

* More clippy fixes

* Update client/statement-store/README.md

Co-authored-by: cheme <emericchevalier.pro@gmail.com>

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <git@kchr.de>

* Removed sstore from node-template

* Sort out data path

* Added offline check

* Removed dispatch_statement

* Renamed into_generic

* Fixed commit placement

* Use HashSet for tracking peers/statements

* fmt

* Use ExtendedHostFunctions

* Fixed benches

* Tweaks

* Apply suggestions from code review

Co-authored-by: cheme <emericchevalier.pro@gmail.com>

* Fixed priority mixup

* Rename

* newtypes for priorities

* Added MAX_TOPICS

* Fixed key filtering logic

* Remove empty entrie

* Removed prefix from signing

* More documentation

* fmt

* Moved store setup from sc-service to node

* Handle maintenance task in sc-statement-store

* Use statement iterator

* Renamed runtime API mod

* fmt

* Remove dump_encoded

* fmt

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <git@kchr.de>

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <git@kchr.de>

* Fixed build after applying review suggestions

* License exceptions

* fmt

* Store options

* Moved pallet consts to config trait

* Removed global priority

* Validate fields when decoding

* Limit validation channel size

* Made a comment into module doc

* Removed submit_encoded

---------

Co-authored-by: cheme <emericchevalier.pro@gmail.com>
Co-authored-by: Bastian Köcher <git@kchr.de>

substrate/bin/node-template/node/Cargo.toml

@@ -28,6 +28,7 @@ sc-telemetry = { version = "4.0.0-dev", path = "../../../client/telemetry" }
 sc-keystore = { version = "4.0.0-dev", path = "../../../client/keystore" }
 sc-transaction-pool = { version = "4.0.0-dev", path = "../../../client/transaction-pool" }
 sc-transaction-pool-api = { version = "4.0.0-dev", path = "../../../client/transaction-pool/api" }
+sc-statement-store = { version = "4.0.0-dev", path = "../../../client/statement-store" }
 sc-consensus-aura = { version = "0.10.0-dev", path = "../../../client/consensus/aura" }
 sp-consensus-aura = { version = "0.10.0-dev", path = "../../../primitives/consensus/aura" }
 sp-consensus = { version = "0.10.0-dev", path = "../../../primitives/consensus/common" }