[ALICE3] Pass trackparcov as reference instead of copy in a3 track utilities

[jesgum]

No description provided.

[github-actions]

O2 linter results: ❌ 13 errors, ⚠️ 2 warnings, 🔕 0 disabled

[vkucera]

What is the rationale behind this memory allocation?

[alibuild]

Error while checking build/O2Physics/code-check for a4f2057 at 2026-07-03 10:12:

## sw/BUILD/O2Physics-code-check-latest/log
--
========== List of issues found ==========
++ echo 'Found 11 errors and 0 warnings.'
Found 11 errors and 0 warnings.
++ [[ 11 -gt 0 ]]
++ cat /sw/BUILD/75d1f593c95edb00bdb4f50bf5c2c4b9eb3cc077/O2Physics-code-check/errors.txt
ALICE3/Core/TrackUtilities.cxx:36:3: error: uninitialized record type: 'params' [cppcoreguidelines-pro-type-member-init,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:38:9: error: variable 's' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:38:12: error: variable 'c' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:38:15: error: variable 'x' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:64:9: error: variable 'sna' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:64:14: error: variable 'csa' is not initialized [cppcoreguidelines-init-variables,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:72:5: error: Value stored to 'length' is never read [clang-analyzer-deadcode.DeadStores,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:90:11: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:91:11: error: do not declare C-style arrays, use 'std::array' instead [modernize-avoid-c-arrays,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:94:5: error: uninitialized record type: 'mom' [cppcoreguidelines-pro-type-member-init,-warnings-as-errors]
ALICE3/Core/TrackUtilities.cxx:100:5: error: uninitialized record type: 'startPoint' [cppcoreguidelines-pro-type-member-init,-warnings-as-errors]
++ [[ 0 -gt 0 ]]
++ [[ 11 -gt 0 ]]
++ exit 1
--

Full log here.