ITS3: add metal layer + fix macros

[f3sch]

Needs #13895 and #13929.

[github-actions]

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[github-actions]

This PR did not have any update in the last 30 days. Is it still needed? Unless further action in will be closed in 5 days.

[alibuild]

Error while checking build/O2/fullCI_slc9 for 60519ab at 2025-04-09 12:28:

## sw/BUILD/O2-latest/log
Error: Input path does not exist or is inaccessible: /response/ITS3ChipResponseData/APTSResponseData/
ninja: build stopped: subcommand failed.

Full log here.

[alibuild]

Error while checking build/O2/fullCI_slc9 for ba028ad at 2025-04-10 11:40:

## sw/BUILD/O2-latest/log
Error: Input path does not exist or is inaccessible: /sw/slc9_x86-64/ITSResponse/v2.0.0-2/response/ITS3ChipResponseData/APTSResponseData/
ninja: build stopped: subcommand failed.

Full log here.

[alibuild]

Error while checking build/O2/fullCI_slc9 for ea84cf6 at 2025-04-10 19:41:

## sw/BUILD/O2Physics-latest/log
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:
Error in cling::AutoLoadingVisitor::InsertIntoAutoLoadingState:


## sw/BUILD/O2-full-system-test-latest/log
Detected critical problem in logfile sim.log


## sw/BUILD/o2checkcode-latest/log
--
========== List of errors found ==========
++ GRERR=0
++ grep -v clang-diagnostic-error error-log.txt
++ grep ' error:'
grep: error-log.txt: binary file matches
++ GRERR=1
++ [[ 1 == 0 ]]
++ mkdir -p /sw/INSTALLROOT/2d61ad979cf5f2431c9eb4885fe3944113d7d0ac/slc9_x86-64/o2checkcode/1.0-local124/etc/modulefiles
++ cat
--

Full log here.

[f3sch]

The error is unrelated @shahor02/@mconcas please merge.