ci(payjoin): isolate funded testnet fixture

.github/workflows/analyze_and_test.yml

@@ -16,6 +16,10 @@ on:
       - '.gitignore'
       - '.git-blame-ignore-revs'
       - '.github/ISSUE_TEMPLATE/**'
+  # The funded Payjoin fixture spends from shared testnet wallets. It does not
+  # run for the concurrent develop stack; workflow_dispatch lets a reviewer run
+  # it for an arbitrary branch.
+  workflow_dispatch:
 
 # Checkout + tests only; no writes to the repo via the token.
 permissions:
@@ -169,6 +173,10 @@ jobs:
         env:
           TEST_ALICE_MNEMONIC: ${{ secrets.ENV_TEST_ALICE_MNEMONIC }}
           TEST_BOB_MNEMONIC: ${{ secrets.ENV_TEST_BOB_MNEMONIC }}
+          # The fixture spends from these two shared wallets. It runs as a final
+          # delivery gate on PRs to main, rather than for every develop PR in a
+          # stack, and can still be run manually for an arbitrary branch.
+          RUN_FUNDED_PAYJOIN_TEST: ${{ github.base_ref == 'main' || github.event_name == 'workflow_dispatch' }}
           SCCACHE_GHA_ENABLED: "true"
           RUSTC_WRAPPER: sccache
           # sccache cannot cache incremental compilation artifacts; disabling

integration_test/payjoin_test.dart

@@ -103,9 +103,10 @@ Future<void> main({bool isInitialized = false}) async {
       receiverMnemonic != null &&
       receiverMnemonic.isNotEmpty &&
       senderMnemonic != null &&
-      senderMnemonic.isNotEmpty;
+      senderMnemonic.isNotEmpty &&
+      Platform.environment['RUN_FUNDED_PAYJOIN_TEST'] == 'true';
   const fixtureSkip =
-      'requires TEST_ALICE_MNEMONIC and TEST_BOB_MNEMONIC (funded testnet wallets)';
+      'requires a PR to main or a manually dispatched CI run with funded testnet wallets';
 
   // Belongs to this file's own Bull.init above, not to the fixtures, so it
   // stays at the root scope and runs even when the funded group is skipped.
@@ -150,13 +151,11 @@ Future<void> main({bool isInitialized = false}) async {
   // are individually skipped still runs its setUpAll and tearDownAll, whereas
   // a skipped group runs neither. Verified against package:test 1.31.
   //
-  // That distinction is what made every fork PR red. GitHub withholds secrets
-  // from pull_request runs on forks, so TEST_ALICE_MNEMONIC/TEST_BOB_MNEMONIC
-  // expand to the empty string — set but empty. The tests below skipped
-  // correctly, yet this setUpAll still ran, and createFromMnemonic rejected a
-  // 1-word mnemonic. Because gen_all_test.dart calls each file's main()
-  // without wrapping it in a group, the failure landed on the root scope of
-  // the aggregated suite and took down the whole integration job.
+  // This also keeps shared funded wallets out of concurrent pull-request jobs.
+  // Every such job otherwise derives the same BIP84 account and broadcasts
+  // consolidation transactions from the same UTXOs, causing RBF conflicts.
+  // The workflow enables this group for delivery PRs to main or manual runs,
+  // not for every branch in a concurrent develop stack.
   //
   // Scoping the hooks to the group also stops them leaking into the other
   // seven aggregated files, which previously inherited this setUp and paid a