Dispute distribution implementation (#3282)

* Dispute protocol.

* Dispute distribution protocol.

* Get network requests routed.

* WIP: Basic dispute sender logic.

* Basic validator determination logic.

* WIP: Getting things to typecheck.

* Slightly larger timeout.

* More typechecking stuff.

* Cleanup.

* Finished most of the sending logic.

* Handle active leaves updates

- Cleanup dead disputes
- Update sends for new sessions
- Retry on errors

* Pass sessions in already.

* Startup dispute sending.

* Provide incoming decoding facilities

and use them in statement-distribution.

* Relaxed runtime util requirements.

We only need a `SubsystemSender` not a full `SubsystemContext`.

* Better usability of incoming requests.

Make it possible to consume stuff without clones.

* Add basic receiver functionality.

* Cleanup + fixes for sender.

* One more sender fix.

* Start receiver.

* Make sure to send responses back.

* WIP: Exposed authority discovery

* Make tests pass.

* Fully featured receiver.

* Decrease cost of `NotAValidator`.

* Make `RuntimeInfo` LRU cache size configurable.

* Cache more sessions.

* Fix collator protocol.

* Disable metrics for now.

* Make dispute-distribution a proper subsystem.

* Fix naming.

* Code style fixes.

* Factored out 4x copied mock function.

* WIP: Tests.

* Whitespace cleanup.

* Accessor functions.

* More testing.

* More Debug instances.

* Fix busy loop.

* Working tests.

* More tests.

* Cleanup.

* Fix build.

* Basic receiving test.

* Non validator message gets dropped.

* More receiving tests.

* Test nested and subsequent imports.

* Fix spaces.

* Better formatted imports.

* Import cleanup.

* Metrics.

* Message -> MuxedMessage

* Message -> MuxedMessage

* More review remarks.

* Add missing metrics.rs.

* Fix flaky test.

* Dispute coordinator - deliver confirmations.

* Send out `DisputeMessage` on issue local statement.

* Unwire dispute distribution.

* Review remarks.

* Review remarks.

* Better docs.

polkadot/Cargo.lock

@@ -5816,7 +5816,6 @@ dependencies = [
  "polkadot-node-subsystem-util",
  "polkadot-primitives",
  "rand 0.8.4",
- "sc-keystore",
  "sc-network",
  "smallvec 1.6.1",
  "sp-application-crypto",
@@ -5944,6 +5943,39 @@ dependencies = [
  "sp-std",
 ]
 
+[[package]]
+name = "polkadot-dispute-distribution"
+version = "0.1.0"
+dependencies = [
+ "assert_matches",
+ "async-trait",
+ "futures 0.3.15",
+ "futures-timer 3.0.2",
+ "lazy_static",
+ "lru",
+ "maplit",
+ "parity-scale-codec",
+ "polkadot-erasure-coding",
+ "polkadot-node-core-runtime-api",
+ "polkadot-node-network-protocol",
+ "polkadot-node-primitives",
+ "polkadot-node-subsystem",
+ "polkadot-node-subsystem-test-helpers",
+ "polkadot-node-subsystem-util",
+ "polkadot-primitives",
+ "rand 0.8.4",
+ "sc-keystore",
+ "sc-network",
+ "smallvec 1.6.1",
+ "sp-application-crypto",
+ "sp-core",
+ "sp-keyring",
+ "sp-keystore",
+ "sp-tracing",
+ "thiserror",
+ "tracing",
+]
+
 [[package]]
 name = "polkadot-erasure-coding"
 version = "0.9.8"
@@ -5970,7 +6002,6 @@ dependencies = [
  "polkadot-primitives",
  "rand 0.8.4",
  "rand_chacha 0.3.1",
- "sc-keystore",
  "sp-application-crypto",
  "sp-consensus-babe",
  "sp-core",
@@ -5995,7 +6026,6 @@ dependencies = [
  "polkadot-node-subsystem-util",
  "polkadot-overseer",
  "polkadot-primitives",
- "sc-authority-discovery",
  "sc-network",
  "sp-consensus",
  "sp-core",
@@ -6350,11 +6380,13 @@ dependencies = [
 name = "polkadot-node-network-protocol"
 version = "0.1.0"
 dependencies = [
+ "async-trait",
  "futures 0.3.15",
  "parity-scale-codec",
  "polkadot-node-jaeger",
  "polkadot-node-primitives",
  "polkadot-primitives",
+ "sc-authority-discovery",
  "sc-network",
  "strum",
  "thiserror",
@@ -6379,6 +6411,7 @@ dependencies = [
  "sp-maybe-compressed-blob",
  "sp-runtime",
  "thiserror",
+ "tracing",
  "zstd",
 ]
 
@@ -6407,9 +6440,13 @@ dependencies = [
  "polkadot-overseer",
  "polkadot-primitives",
  "polkadot-statement-table",
+ "sc-keystore",
  "sc-network",
  "smallvec 1.6.1",
+ "sp-application-crypto",
  "sp-core",
+ "sp-keyring",
+ "sp-keystore",
  "tracing",
 ]
 
@@ -6828,6 +6865,7 @@ dependencies = [
  "polkadot-availability-recovery",
  "polkadot-client",
  "polkadot-collator-protocol",
+ "polkadot-dispute-distribution",
  "polkadot-gossip-support",
  "polkadot-network-bridge",
  "polkadot-node-collation-generation",