ci: Silence UBSan diagnostics in the ubsan build config

The debian-trixie-clang-22-amd64-debug-ubsan job logs many non-fatal
UBSan `runtime error:` lines (it passes because halt_on_error=false).
These come from two places that needed different fixes.

Build-time: the protocol code-gen and build steps run instrumented
dependency tools (protoc, grpc) before the "Set sanitizer options" step
exported UBSAN_OPTIONS, so the suppression list never applied to them.
Move that step to run right after "Configure CMake" — before code-gen
and build — reusing the existing ${GITHUB_WORKSPACE}/$GITHUB_ENV
mechanism so the path resolves correctly inside the container job.

Test-time: extend ubsan.supp. unsigned-integer-overflow and
float-divide-by-zero are separate checks, not part of the `undefined`
group, so undefined:<x> keys do not cover them. Add broad
unsigned-integer-overflow keys for absl and protobuf (matching the
existing boost handling), a few libstdc++ headers, and narrowly
function-scoped entries for rippled's intentional wraparound (hashing,
PRNG, counters guarded by explicit overflow checks) plus test
arithmetic, each with a rationale comment.

Fix the one genuine issue in code: a diagnostic JLOG line in
doLedgerGrpc divided the extract time by the object / transaction
counts, which are zero for an empty ledger. Guard the per-item rates.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.github/workflows/reusable-build-test-config.yml

@@ -164,6 +164,26 @@ jobs:
               ${CMAKE_ARGS} \
               ..
 
+      # Export the sanitizer options before any instrumented binary runs. The
+      # protocol code-gen and build steps below invoke instrumented dependency
+      # tools (protoc, grpc), so setting UBSAN_OPTIONS here lets the UBSan
+      # suppression list silence their diagnostics too, not just at test time.
+      # GITHUB_WORKSPACE (not the github.workspace context) is used so the path
+      # resolves correctly inside the container job.
+      - name: Set sanitizer options
+        if: ${{ !inputs.build_only && env.SANITIZERS_ENABLED == 'true' }}
+        env:
+          CONFIG_NAME: ${{ inputs.config_name }}
+        run: |
+          ASAN_OPTS="include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-asan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/asan.supp"
+          if [[ "${CONFIG_NAME}" == *gcc* ]]; then
+              ASAN_OPTS="${ASAN_OPTS}:alloc_dealloc_mismatch=0"
+          fi
+          echo "ASAN_OPTIONS=${ASAN_OPTS}" >>${GITHUB_ENV}
+          echo "TSAN_OPTIONS=include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-tsan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/tsan.supp" >>${GITHUB_ENV}
+          echo "UBSAN_OPTIONS=include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-ubsan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/ubsan.supp" >>${GITHUB_ENV}
+          echo "LSAN_OPTIONS=include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-lsan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/lsan.supp" >>${GITHUB_ENV}
+
       - name: Check protocol autogen files are up-to-date
         working-directory: ${{ env.BUILD_DIR }}
         env:
@@ -279,20 +299,6 @@ jobs:
         run: |
           ./xrpld --version | grep libvoidstar
 
-      - name: Set sanitizer options
-        if: ${{ !inputs.build_only && env.SANITIZERS_ENABLED == 'true' }}
-        env:
-          CONFIG_NAME: ${{ inputs.config_name }}
-        run: |
-          ASAN_OPTS="include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-asan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/asan.supp"
-          if [[ "${CONFIG_NAME}" == *gcc* ]]; then
-              ASAN_OPTS="${ASAN_OPTS}:alloc_dealloc_mismatch=0"
-          fi
-          echo "ASAN_OPTIONS=${ASAN_OPTS}" >>${GITHUB_ENV}
-          echo "TSAN_OPTIONS=include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-tsan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/tsan.supp" >>${GITHUB_ENV}
-          echo "UBSAN_OPTIONS=include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-ubsan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/ubsan.supp" >>${GITHUB_ENV}
-          echo "LSAN_OPTIONS=include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-lsan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/lsan.supp" >>${GITHUB_ENV}
-
       - name: Run the separate tests
         if: ${{ !inputs.build_only }}
         working-directory: ${{ runner.os == 'Windows' && format('{0}/{1}', env.BUILD_DIR, inputs.build_type) || env.BUILD_DIR }}