collect included disputes from on-chain (#3924)

* dummy: impl another runtime API

* query the on chain disputes, and inform self

* make use of the refactor

* minro

* SPLIT ME

* write dispute values

* wip

* impl for all runtimes

* chore: fmt

* [] -> get

* fixup mock runtime

* fixup

* fixup discovery for overseer init

* chore: fmt

* spellcheck

* rename imported_on_chain_disputes -> on_chain_votes

* reduction

* make it mockable

* rename and refactor

* don't query on chain info if it's not needed

* yikes

* fmt

* fix test

* minimal fix for existing tests

* attempt to fetch the session info from the rolling window before falling back

* moved

* comments

* comments

* test for backing votes

* rename

* Update runtime/polkadot/src/lib.rs

* chore: spellcheck + dict

* chore: fmt

* fixup cache size

* add warning

* logging, rationale, less defense

* introduce new unchecked, that still checks in debug builds

* fix

* draft alt approach

* fix unused imports

* include the session

* Update node/core/dispute-coordinator/src/real/mod.rs

Co-authored-by: Robert Habermeier <rphmeier@gmail.com>

* provide where possible

* expand comment

* fixin

* fixup

* ValidityVote <-> ValidityAttestation <-> CompactStatement has a 1:1 representation

* mark TODO

* Update primitives/src/v1/mod.rs

Co-authored-by: Robert Habermeier <rphmeier@gmail.com>

* address review comments

* update docs

Co-authored-by: Robert Habermeier <rphmeier@gmail.com>

polkadot/node/core/runtime-api/src/lib.rs

@@ -143,6 +143,8 @@ where
 				.cache_inbound_hrmp_channel_contents((relay_parent, para_id), contents),
 			CurrentBabeEpoch(relay_parent, epoch) =>
 				self.requests_cache.cache_current_babe_epoch(relay_parent, epoch),
+			FetchOnChainVotes(relay_parent, scraped) =>
+				self.requests_cache.cache_on_chain_votes(relay_parent, scraped),
 		}
 	}
 
@@ -209,6 +211,8 @@ where
 					.map(|sender| Request::InboundHrmpChannelsContents(id, sender)),
 			Request::CurrentBabeEpoch(sender) =>
 				query!(current_babe_epoch(), sender).map(|sender| Request::CurrentBabeEpoch(sender)),
+			Request::FetchOnChainVotes(sender) =>
+				query!(on_chain_votes(), sender).map(|sender| Request::FetchOnChainVotes(sender)),
 		}
 	}
 
@@ -342,6 +346,7 @@ where
 		Request::InboundHrmpChannelsContents(id, sender) =>
 			query!(InboundHrmpChannelsContents, inbound_hrmp_channels_contents(id), sender),
 		Request::CurrentBabeEpoch(sender) => query!(CurrentBabeEpoch, current_epoch(), sender),
+		Request::FetchOnChainVotes(sender) => query!(FetchOnChainVotes, on_chain_votes(), sender),
 	}
 }