[PWGCF] add centrality and multiplicity correlation cuts and event selection cuts

[pykuan]

• add Run 3 general event selection cuts
• add eta-gap two-particle correlations
• add event-by-event 2- and 4-particle correlation histograms
• add min/max monitoring for correlation values
• add denominator checks for multiparticle correlations
• update four-particle harmonic combinations to include v2^2v2^2
• add separate multiplicity correlation cuts for FT0C-FT0M, FT0C-FV0A, and FT0M-FV0A
• add estimator-dependent multiplicity histogram binning
• store correlation cut boundaries as TF1 objects
• add configurable binning for two- and four-particle correlation histograms

[github-actions]

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

[alibuild]

Error while checking build/O2Physics/code-check for 44afc3c at 2026-07-19 15:38:

## sw/BUILD/O2Physics-code-check-latest/log
--
========== List of issues found ==========
++ echo 'Found 13 errors and 0 warnings.'
Found 13 errors and 0 warnings.
++ [[ 13 -gt 0 ]]
++ cat /sw/BUILD/36843dbd0e8067ed13ea2d18b2048105c9b04ca5/O2Physics-code-check/errors.txt
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:580:9: error: do not use 'else' after 'return' [readability-else-after-return,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:588:11: error: do not use 'else' after 'return' [readability-else-after-return,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:595:11: error: do not use 'else' after 'return' [readability-else-after-return,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:602:11: error: do not use 'else' after 'return' [readability-else-after-return,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:1604:9: error: variable 'nBinsCent' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:1605:11: error: variable 'minCent' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:1606:11: error: variable 'maxCent' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:1608:9: error: variable 'nBinsXMult' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:1609:11: error: variable 'minXMult' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:1610:11: error: variable 'maxXMult' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:1611:9: error: variable 'nBinsYMult' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:1612:11: error: variable 'minYMult' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:1613:11: error: variable 'maxYMult' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
++ [[ 0 -gt 0 ]]
++ [[ 13 -gt 0 ]]
++ exit 1
--

Full log here.

[abilandz]

@pykuan : Thanks for the new PR - please fix all "Required" checks that are failing, and alongside that, whatever you can from the rest. Some errors are really easy to fix.

[alibuild]

Error while checking build/O2Physics/staging for aabc1ca at 2026-07-19 15:56:

## sw/BUILD/O2Physics-latest/log
/sw/SOURCES/O2Physics/slc9_x86-64-slc9_x86-64/0/PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:596:3: error: control reaches end of non-void function [-Werror=return-type]
ninja: build stopped: subcommand failed.

Full log here.

[alibuild]

Error while checking build/O2Physics/o2 for aabc1ca at 2026-07-19 16:01:

## sw/BUILD/O2Physics-latest/log
/sw/SOURCES/O2Physics/slc9_x86-64-slc9_x86-64/0/PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:596:3: error: control reaches end of non-void function [-Werror=return-type]
ninja: build stopped: subcommand failed.

Full log here.

[alibuild]

Error while checking build/O2Physics/code-check for aabc1ca at 2026-07-19 16:06:

## sw/BUILD/O2Physics-code-check-latest/log
--
========== List of issues found ==========
++ echo 'Found 1 errors and 0 warnings.'
Found 1 errors and 0 warnings.
++ [[ 1 -gt 0 ]]
++ cat /sw/BUILD/f750b5839da2b18eac87f6bbeb51fee42a9f8214/O2Physics-code-check/errors.txt
PWGCF/MultiparticleCorrelations/Tasks/multiparticleCumulants.cxx:596:3: error: non-void function does not return a value in all control paths [clang-diagnostic-return-type,-warnings-as-errors]
++ [[ 0 -gt 0 ]]
++ [[ 1 -gt 0 ]]
++ exit 1
--

Full log here.