fix(ecstore): resolve erasure parity per pool (#4801) (#5015)

* fix(ecstore): add fallible erasure construction

(cherry picked from commit bd148b20f7)

* fix(ecstore): resolve storage parity per pool

(cherry picked from commit c05c2cb24b)

* fix(ecstore): keep carved per-pool parity core self-contained on main

Fixups so the cherry-picked fallible-erasure + per-pool-parity core builds standalone on current main without the excluded scope-creep commits:
- runtime/sources.rs: re-add backend_storage_class_parities (removed by the per-pool commit; its rebalance caller was updated in an unrelated reporting commit that was left out). Reimplemented over the snapshot API, behavior-identical.
- config/mod.rs: rename the storage-class publish test module (main independently added a mod tests, so the cherry-pick collided).
- rustfs storage_api.rs + startup_storage.rs: route the storage-class ENV consts through the startup storage facade and use a local const for the erasure-set-drive-count env name, satisfying the layer/facade guardrail (main's guardrail is stricter than when the core was authored).

* fix(ecstore): use struct-init in erasure test helper to satisfy clippy field_reassign_with_default

The cherry-picked fallible-erasure commit's `erasure_with_invalid_dimensions` test helper built `Erasure` via `default()` then reassigned fields, which trips `clippy::field_reassign_with_default` under `-D warnings` (only surfaced by `--all-targets`, which lints test code). #4977 fixed this in a later commit that was not part of the carved core. Use struct-init with `..Default::default()`, matching #4977's final form.

* fix(rustfs): gate the test-only storage-class ENV facade re-export behind cfg(test)

The ENV constants (INLINE_BLOCK_ENV/OPTIMIZE_ENV/RRS_ENV/STANDARD_ENV) re-exported through the startup storage facade are only consumed by a #[cfg(test)] test in startup_storage.rs, so in a non-test lib build the re-export is unused and trips -D unused-imports under clippy --all-targets. Gate it with #[cfg(test)], matching #4977's final form.

---------

Co-authored-by: cxymds <cxymds@gmail.com>

scripts/check_architecture_migration_rules.sh

@@ -140,6 +140,7 @@ ECSTORE_STORAGE_API_ROOT_REEXPORT_HITS_FILE="${TMP_DIR}/ecstore_storage_api_root
 ECSTORE_STORAGE_API_ROOT_CONSUMER_HITS_FILE="${TMP_DIR}/ecstore_storage_api_root_consumer_hits.txt"
 ECSTORE_TEST_DIRECT_API_HITS_FILE="${TMP_DIR}/ecstore_test_direct_api_hits.txt"
 ECSTORE_BENCH_DIRECT_API_HITS_FILE="${TMP_DIR}/ecstore_bench_direct_api_hits.txt"
+ERASURE_PANICKING_CONSTRUCTOR_HITS_FILE="${TMP_DIR}/erasure_panicking_constructor_hits.txt"
 LOCAL_STORAGE_API_RAW_CONTRACT_PATH_HITS_FILE="${TMP_DIR}/local_storage_api_raw_contract_path_hits.txt"
 STORE_API_DELETE_DTO_REEXPORTS_FILE="${TMP_DIR}/store_api_delete_dto_reexports.txt"
 STORE_API_DELETE_DTO_INTERNAL_HITS_FILE="${TMP_DIR}/store_api_delete_dto_internal_hits.txt"
@@ -1151,6 +1152,54 @@ if [[ -s "$ECSTORE_BENCH_DIRECT_API_HITS_FILE" ]]; then
   report_failure "ECStore benches must route ECStore and storage-api symbols through crates/ecstore/benches/storage_api/mod.rs: $(paste -sd '; ' "$ECSTORE_BENCH_DIRECT_API_HITS_FILE")"
 fi
 
+(
+  cd "$ROOT_DIR"
+  find rustfs/src crates -type f -name '*.rs' -print0 |
+    xargs -0 perl -ne '
+      next unless $ARGV =~ m{^(?:rustfs/src/|crates/[^/]+/src/)};
+      if (!defined $current_file || $ARGV ne $current_file) {
+        $current_file = $ARGV;
+        $line = 0;
+        $pending_test_item = 0;
+        $in_test_item = 0;
+        $test_indent = "";
+      }
+      $line++;
+      if ($in_test_item) {
+        $in_test_item = 0 if /^(\s*)}\s*[\]),;]*\s*(?:\/\/.*)?$/ && $1 eq $test_indent;
+        next;
+      }
+      if (/^(\s*)#\s*\[\s*cfg\s*\(\s*test\s*\)\s*\]\s*(.*)$/) {
+        $test_indent = $1;
+        my $item = $2;
+        if ($item =~ /^\s*(?:\/\/.*)?$/) {
+          $pending_test_item = 1;
+        } elsif ($item !~ /;\s*(?:\/\/.*)?$/ && $item =~ /\{/ && $item !~ /}\s*(?:\/\/.*)?$/) {
+          $in_test_item = 1;
+        } elsif ($item !~ /;\s*(?:\/\/.*)?$/ && $item !~ /\{/) {
+          $pending_test_item = 1;
+        }
+        next;
+      }
+      if ($pending_test_item) {
+        if (/;\s*(?:\/\/.*)?$/) {
+          $pending_test_item = 0;
+        } elsif (/\{/) {
+          $pending_test_item = 0;
+          $in_test_item = 1 unless /}\s*(?:\/\/.*)?$/;
+        }
+        next;
+      }
+      if (/^\s*(?!\/\/).*\bErasure::new(?:_with_options)?\s*\(/) {
+        print "$ARGV:$line:$_";
+      }
+    ' || true
+) >"$ERASURE_PANICKING_CONSTRUCTOR_HITS_FILE"
+
+if [[ -s "$ERASURE_PANICKING_CONSTRUCTOR_HITS_FILE" ]]; then
+  report_failure "production code must use fallible Erasure constructors: $(paste -sd '; ' "$ERASURE_PANICKING_CONSTRUCTOR_HITS_FILE")"
+fi
+
 (
   cd "$ROOT_DIR"
   find crates/ecstore/src -type f -name '*.rs' -print0 |