fix(ci): serialize Pi jobs; valid XMR fixture after F4

Overlapping Actions used a fixed docker name onionwire-ci (Conflict)
and OOM-killed with 137. Unique run_id names + one-at-a-time
concurrency. F1 ingest test still used 8+B*94 which F4 checksums reject.

.forgejo/workflows/ci.yml

@@ -8,12 +8,18 @@ on:
   pull_request:
   workflow_dispatch:
 
+# One cargo job on the Pi at a time. Overlapping PR+main runs shared the
+# container name `onionwire-ci` (docker Conflict) and OOM-killed with 137.
+concurrency:
+  group: onionwire-ci-pi
+  cancel-in-progress: false
+
 env:
   CARGO_TERM_COLOR: never
   RUST_IMAGE: rust:1.91-bookworm
   CARGO_REGISTRY_VOLUME: onionwire-cargo-registry
   CARGO_TARGET_VOLUME: onionwire-target-ci
-  BUILD_CONTAINER: onionwire-ci
+  BUILD_CONTAINER: onionwire-ci-${{ github.run_id }}
 
 jobs:
   test:

.forgejo/workflows/release.yml

@@ -22,7 +22,7 @@ env:
   RUST_IMAGE: rust:1.91-bookworm
   CARGO_REGISTRY_VOLUME: onionwire-cargo-registry
   CARGO_TARGET_VOLUME: onionwire-target-aarch64
-  BUILD_CONTAINER: onionwire-release-build
+  BUILD_CONTAINER: onionwire-release-build-${{ github.run_id }}
 
 jobs:
   aarch64:

tests/wallet.rs

@@ -17,7 +17,9 @@ fn row(txid: &str, amount: &str, address: &str) -> TransferRow {
 }
 
 fn xmr_addr() -> String {
-    format!("8{}", "B".repeat(94))
+    // Same documented mainnet standard as tests/pay.rs — F4 checksums this.
+    "4AdUndXHHZ6cfufTMvppY6JwXNouMBzSkbLYfpAV5Usx3skxNgYeYTRj5UzqtReoS44qo9mtmXCqY45DJ852K5Jv2684Rge"
+        .to_string()
 }
 
 fn json_rpc_ok(result: &str) -> String {