Revert "Fixes Wires objects as wire labels bug (#6933)"

[mlxd]

This reverts commit e0b2174.

Before submitting

Please complete the following checklist when submitting a PR:

• All new features must include a unit test.
  If you've fixed a bug or added code that should be tested, add a test to the
  test directory!

• All new functions and code must be clearly commented and documented.
  If you do make documentation changes, make sure that the docs build and
  render correctly by running make docs.

• Ensure that the test suite passes, by running make test.

• Add a new entry to the doc/releases/changelog-dev.md file, summarizing the
  change, and including a link back to the PR.

• The PennyLane source code conforms to
  PEP8 standards.
  We check all of our code against Pylint.
  To lint modified files, simply pip install pylint, and then
  run pylint pennylane/path/to/file.py.

When all the above are checked, delete everything above the dashed
line and fill in the pull request template.

---

Context: Due to non-negligible performance impacts, PR #6933 is to be reverted. Flattening each wire contents introduced overheads between 5-60% in benchmarking, and will be reassessed for support in a follow-up release.

Description of the Change: As above.

Benefits: Restores lost performance.

Possible Drawbacks: Reintroduces incompatibility for nesting of wires

Related GitHub Issues:
[sc-87017]

[andrijapau]

So long 🫡 , thanks both for the help here. 🥇

Excited to see how we can improve on it in Q2 😎 ❗

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.62%. Comparing base (35f705f) to head (5d8534d).
Report is 6 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff            @@
##           master    #7136    +/-   ##
========================================
  Coverage   99.62%   99.62%            
========================================
  Files         503      506     +3     
  Lines       49024    49366   +342     
========================================
+ Hits        48839    49181   +342     
  Misses        185      185            

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[JerryChen97]

Happy to revert now that we do not have a better solution yet

[andrijapau]

🫡

'til we meet again.

[jzaia18]

Looks good! Nice teamwork, y'all c: