[PWGLF] Fix bug + add feeddown QA histograms

[romainschotter]

• fix bug (use |= instead of BITSET)
• Add feeddown QA histograms

[github-actions]

O2 linter results: ❌ 0 errors, ⚠️ 44 warnings, 🔕 0 disabled

[alibuild]

Auto-approving on behalf of @romainschotter.

[alibuild]

Error while checking build/O2Physics/staging for eed5ac4 at 2026-10-03 15:59:

No log files found

Full log here.

[alibuild]

Error while checking build/O2Physics/o2 for eed5ac4 at 2026-10-03 16:00:

No log files found

Full log here.

[alibuild]

Error while checking build/O2Physics/code-check for eed5ac4 at 2026-10-03 16:08:

## sw/BUILD/O2Physics-code-check-latest/log
--
========== List of issues found ==========
++ echo 'Found 1 errors and 148 warnings.'
Found 1 errors and 148 warnings.
++ [[ 1 -gt 0 ]]
++ cat /sw/BUILD/be30ecfdbf49f41a0574b48abea969782417d767/O2Physics-code-check/errors.txt
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:3554:54: error: no header providing "TObject" is directly included [misc-include-cleaner,-warnings-as-errors]
++ [[ 148 -gt 0 ]]
++ cat /sw/BUILD/be30ecfdbf49f41a0574b48abea969782417d767/O2Physics-code-check/warnings.txt
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:91:9: warning: function-like macro 'BITSET' used; consider a 'constexpr' template function [cppcoreguidelines-macro-usage]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:92:9: warning: function-like macro 'BITCHECK' used; consider a 'constexpr' template function [cppcoreguidelines-macro-usage]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:103:8: warning: constructor does not initialize these fields: ccdb [cppcoreguidelines-pro-type-member-init]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:187:20: warning: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:205:67: warning: do not implicitly decay an array into a pointer; consider using gsl::array_view or an explicit cast instead [cppcoreguidelines-pro-bounds-array-to-pointer-decay]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:474:16: warning: redundant boolean literal in conditional assignment [readability-simplify-boolean-expr]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1109:11: warning: implicit conversion 'int' -> 'bool' [readability-implicit-bool-conversion]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1117:11: warning: implicit conversion 'int' -> 'bool' [readability-implicit-bool-conversion]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1142:24: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1144:23: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1146:27: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1296:11: warning: implicit conversion 'int' -> 'bool' [readability-implicit-bool-conversion]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1376:11: warning: do not use 'else' after 'return' [readability-else-after-return]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1411:54: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1436:22: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1438:18: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1440:17: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1451:46: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1453:45: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1464:47: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1466:50: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1468:61: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1470:61: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1472:45: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1474:53: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1479:54: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1482:55: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1489:117: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1491:116: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1494:107: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1496:106: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1511:78: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1516:78: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1525:116: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1532:117: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1536:79: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1538:79: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1540:79: warning: statement should be inside braces [readability-braces-around-statements]
PWGLF/Tasks/Strangeness/derivedlambdakzeroanalysis.cxx:1542:79: warning: statement should be inside braces [readability-braces-around-statements]
[0 more errors; see full log]

Full log here.

[vkucera]

@romainschotter You have errors. Please fix them.