CAExtension rebase onto 15_1_0_pre4

[bfonta]

Recent developments on extending the CA algorithm for the first three layers of the outer tracker have been rebased onto release 15_1_0_pre4 (technically 15_1_X_2025-06-19-2300). It includes the following developments, in order:

• A More Flexible And Lightweight CA #47611
• The NGT IDRIS-CAEXT branch, which implements the CA extension
• This commit from @Parsifal-2045

PR validation:

I run the following cmsDriver.py commands for both the branch included in this PR ("pre4") and the same commits rebased onto 15_1_0_pre3 ("pre3"), where I only listed the first file:

NEVENTS=1000
PROCMOD="alpaka" 
function mystep2() {
	cmsDriver.py step2 -s L1P2GT,HLT:NGTScouting,VALIDATION:@hltValidation \
				 --conditions auto:phase2_realistic_T33 \
				 --datatier GEN-SIM-DIGI-RAW,DQMIO \
				 -n ${NEVENTS} \
				 --eventcontent FEVTDEBUGHLT,DQMIO \
				 --geometry ExtendedRun4D110 \
				 --era Phase2C17I13M9 \
				 --procModifier ${PROCMOD} \
				 --filein file:/eos/cms/store/relval/CMSSW_15_1_0_pre3/RelValTTbar_14TeV/GEN-SIM-DIGI-RAW/PU_150X_mcRun4_realistic_v1_STD_Run4D110_PU-v1/2590000//00c675dc-1517-4af7-8dd4-841e0668fefe.root,...
				 --fileout file:step2.root \
				 --nThreads 24 \
				 --process HLTX \
				 --inputCommands='keep *, drop *_hlt*_*_HLT, drop triggerTriggerFilterObjectWithRefs_l1t*_*_HLT'
}

function mystep3() {
	cmsDriver.py step3 -s HARVESTING:@hlt+@hltValidation \
				 --conditions auto:phase2_realistic_T33 \
				 --mc \
				 --geometry ExtendedRun4D110 \
				 --scenario pp \
				 --filetype DQM \
				 --era Phase2C17I13M9 \
				 -n ${NEVENTS}  \
				 --filein file:step2_inDQM.root \
				 --fileout file:step3.root
}

mystep2 && mystep3

The validation plots are available here. As an example:

Note: The efficiency is below what the extension can currently provide since this PR was not included (cut on the transverse impact parameter).

[cmsbuild]

cms-bot internal usage

[cmsbuild]

-code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-48471/45397

ERROR: Unable to merge PR.

See log https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-48471/45397/cms-checkout-topic.log