Prepare PVFs if node is a validator in the next session (#4791)

Closes #4324
- On every active leaf candidate-validation subsystem checks if the node
is the next session authority.
- If it is, it fetches backed candidates and prepares unknown PVFs.
- We limit number of PVFs per block to not overload subsystem.

.gitlab/pipeline/zombienet/polkadot.yml

@@ -276,6 +276,14 @@ zombienet-polkadot-smoke-0004-coretime-smoke-test:
       --local-dir="${LOCAL_DIR}/smoke"
       --test="0004-coretime-smoke-test.zndsl"
 
+zombienet-polkadot-smoke-0005-precompile-pvf-smoke:
+  extends:
+    - .zombienet-polkadot-common
+  script:
+    - /home/nonroot/zombie-net/scripts/ci/run-test-local-env-manager.sh
+      --local-dir="${LOCAL_DIR}/smoke"
+      --test="0005-precompile-pvf-smoke.zndsl"
+
 zombienet-polkadot-misc-0001-parachains-paritydb:
   extends:
     - .zombienet-polkadot-common

polkadot/node/core/candidate-validation/Cargo.toml

@@ -13,6 +13,8 @@ workspace = true
 async-trait = { workspace = true }
 futures = { workspace = true }
 futures-timer = { workspace = true }
+sp-keystore = { workspace = true }
+sp-application-crypto = { workspace = true }
 gum.workspace = true
 gum.default-features = true
 sp-maybe-compressed-blob.workspace = true