refactor(standard-contracts): switch pinning to v4-style build-time tarball substitution

Replaces the per-contract pinned JSON + sha256 reproducibility test with the same
mechanism v4 uses for protocol contracts: a single committed
pinned-standard-contracts.tar.gz whose presence at build time causes
noir-contracts/bootstrap.sh to extract the pinned artifacts into target/ and skip
recompilation of contracts under contracts/standard/.

The tarball is intentionally not committed in this PR. Its absence makes the
extraction block a no-op on next; the mechanism activates when a release branch
(e.g. v5) is cut and someone runs `./bootstrap.sh pin-standard-build` and commits
the resulting tarball.

Adds:
  - noir-projects/noir-contracts/standard_contracts.json (manifest mirroring
    protocol_contracts.json)
  - extraction block in build() gated on tarball presence
  - pin-standard-build function + case arm

Removes:
  - yarn-project/standard-contracts/src/reproducibility.test.ts
  - yarn-project/standard-contracts/src/pinned/*.json (three pinned artifacts)
  - the matching .prettierignore entry

Author: dbanks12

noir-projects/noir-contracts/bootstrap.sh

@@ -144,7 +144,17 @@ function build {
 
   if [ "$#" -eq 0 ]; then
     rm -rf target
+    mkdir -p target
     local contracts=$(grep -oP "(?<=$folder_name/)[^\"]+" Nargo.toml)
+
+    # If a pinned standard-contracts archive is present, extract it into target/ and skip
+    # recompilation of those contracts. The archive is only committed on release branches; on
+    # next it is absent and this block is a no-op (everything compiles fresh).
+    if [ -f pinned-standard-contracts.tar.gz ]; then
+      echo_stderr "Using pinned-standard-contracts.tar.gz for pinned standard contracts."
+      tar xzf pinned-standard-contracts.tar.gz -C target
+      contracts=$(echo "$contracts" | grep -vE "^standard/")
+    fi
   else
     local contracts="$@"
   fi
@@ -217,6 +227,19 @@ function format {
   $NARGO fmt
 }
 
+# Force-builds standard contracts and tar-balls their artifacts into pinned-standard-contracts.tar.gz.
+# Run this at release-branch cut time, then commit the resulting tarball to the release branch.
+# Mirrors the v4 `pin-build` mechanism that pins protocol contracts.
+function pin-standard-build {
+  rm -f pinned-standard-contracts.tar.gz
+  local standard_contracts=$(grep -oP '(?<=contracts/)[^"]+' Nargo.toml | grep "^standard/")
+  build $standard_contracts
+  local standard_artifacts=$(jq -r '.[]' standard_contracts.json | sed 's/$/.json/')
+  echo_stderr "Creating pinned-standard-contracts.tar.gz..."
+  (cd target && tar czf ../pinned-standard-contracts.tar.gz $standard_artifacts)
+  echo_stderr "Done. pinned-standard-contracts.tar.gz created. Commit it to pin these artifacts."
+}
+
 case "$cmd" in
   "clean-keys")
     for artifact in target/*.json; do
@@ -231,6 +254,9 @@ case "$cmd" in
   "compile")
     VERBOSE=${VERBOSE:-1} build "$@"
     ;;
+  "pin-standard-build")
+    pin-standard-build
+    ;;
   *)
     default_cmd_handler "$@"
     ;;

noir-projects/noir-contracts/standard_contracts.json

@@ -0,0 +1,5 @@
+[
+  "auth_registry_contract-AuthRegistry",
+  "public_checks_contract-PublicChecks",
+  "multi_call_entrypoint_contract-MultiCallEntrypoint"
+]

yarn-project/.prettierignore

@@ -5,7 +5,6 @@ noir-contracts.js/**/*.json
 noir-contracts.js/src
 noir-test-contracts.js/**/*.json
 noir-test-contracts.js/src
-standard-contracts/src/**/pinned/*.json
 noir-protocol-circuits-types/src/target/*
 *.md
 end-to-end/src/fixtures/dumps/*.json