[PWGHF] taskFlow.cxx: Add the use of reassociated MFT tracks for same event

[AlexianL]

In this PR :

• I added the possibility to run with MFT tracks (in same event) that have been reassociated to the collisions with the closest DCAxy of the track. This is done with the new "fillCorrelationsReassociated" and "processSameTpcMft....Reassociated" functions,
• I added the possibility to do a cut on MFT ambiguous tracks,
• I also added new QA plots for reassociated MFT tracks

[github-actions]

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

[alibuild]

Error while checking build/O2Physics/o2 for c664f8f at 2025-07-30 11:23:

## sw/BUILD/O2Physics-latest/log
/sw/SOURCES/O2Physics/12327-slc9_x86-64/0/PWGHF/HFC/Tasks/taskFlow.cxx:104:15: error: 'ccdb' is not a member of 'o2'
/sw/SOURCES/O2Physics/12327-slc9_x86-64/0/PWGHF/HFC/Tasks/taskFlow.cxx:104:37: error: template argument 1 is invalid
ninja: build stopped: subcommand failed.

Full log here.

[vkucera]

Please compile your branch before you make or update a PR.

[vkucera]

Thanks @AlexianL , looks good to me.
@apalasciano @deepathoms please have a look.

[fgrosa]

Thanks @AlexianL , looks good to me. @apalasciano @deepathoms please have a look.

Hi @vkucera, Antonio and Jonghan are on vacation, so I would merge it not to delay too much @AlexianL's work. Thanks for your review!