ci(e2e): keep the relay version markers in the e2e build artifact (#15303)

build-relay.mjs writes each relay's marker as out/relay/<platform>/.version,
and upload-artifact excludes dotfiles unless include-hidden-files is set. The
markers were therefore stripped from e2e-build-out, so every consumer that
actually starts a relay failed with:

  Orca's local relay build is missing its version marker at
  out/relay/linux-x64/.version

This stayed latent because the sharded e2e lane never sets ORCA_E2E_SSH_DOCKER,
so its SSH specs skip instead of touching the relay. The changed-specs lane does
set it whenever a changed spec needs Docker SSH, which is why the failure only
appears on PRs that touch SSH-adjacent code.

.github/workflows/e2e.yml

@@ -86,6 +86,10 @@ jobs:
         with:
           name: e2e-build-out
           path: out/
+          # Why: build-relay.mjs writes each relay's marker as `out/relay/<platform>/.version`,
+          # and upload-artifact drops dotfiles by default — consumers then fail SSH specs with
+          # "local relay build is missing its version marker".
+          include-hidden-files: true
           retention-days: 1
           if-no-files-found: error