Remove fabric legacy CLI

[justusschock]

What does this PR do?

Removes legacy support for lightning run model in favor of fabric run.
Currently, depending on the installation order, lightning run might go from legacy CLI here to the lightning-sdk including intermediate numpy and torch imports slowing down the CLI drastically.

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📚 Documentation preview 📚: https://pytorch-lightning--20588.org.readthedocs.build/en/20588/

[github-actions]

⚡ Required checks status: All passing 🟢

Groups summary

🟢 pytorch_lightning: Tests workflow

Check ID	Status
pl-cpu (macOS-14, lightning, 3.9, 2.1, oldest)	success	✅
pl-cpu (macOS-14, lightning, 3.10, 2.1)	success	✅
pl-cpu (macOS-14, lightning, 3.11, 2.2.2)	success	✅
pl-cpu (macOS-14, lightning, 3.11, 2.3)	success	✅
pl-cpu (macOS-14, lightning, 3.12.7, 2.4.1)	success	✅
pl-cpu (macOS-14, lightning, 3.12.7, 2.5.1)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.9, 2.1, oldest)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.10, 2.1)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.11, 2.2.2)	success	✅
pl-cpu (ubuntu-20.04, lightning, 3.11, 2.3)	success	✅
pl-cpu (ubuntu-22.04, lightning, 3.12.7, 2.4.1)	success	✅
pl-cpu (ubuntu-22.04, lightning, 3.12.7, 2.5.1)	success	✅
pl-cpu (windows-2022, lightning, 3.9, 2.1, oldest)	success	✅
pl-cpu (windows-2022, lightning, 3.10, 2.1)	success	✅
pl-cpu (windows-2022, lightning, 3.11, 2.2.2)	success	✅
pl-cpu (windows-2022, lightning, 3.11, 2.3)	success	✅
pl-cpu (windows-2022, lightning, 3.12.7, 2.4.1)	success	✅
pl-cpu (windows-2022, lightning, 3.12.7, 2.5.1)	success	✅
pl-cpu (macOS-14, pytorch, 3.9, 2.1)	success	✅
pl-cpu (ubuntu-20.04, pytorch, 3.9, 2.1)	success	✅
pl-cpu (windows-2022, pytorch, 3.9, 2.1)	success	✅
pl-cpu (macOS-14, pytorch, 3.12.7, 2.5.1)	success	✅
pl-cpu (ubuntu-22.04, pytorch, 3.12.7, 2.5.1)	success	✅
pl-cpu (windows-2022, pytorch, 3.12.7, 2.5.1)	success	✅

These checks are required after the changes to src/lightning/fabric/cli.py.

🟢 pytorch_lightning: Azure GPU

Check ID	Status
pytorch-lightning (GPUs) (testing Lightning | latest)	success	✅
pytorch-lightning (GPUs) (testing PyTorch | latest)	success	✅

These checks are required after the changes to src/lightning/__setup__.py, src/lightning/fabric/cli.py.

🟢 pytorch_lightning: Benchmarks

Check ID	Status
lightning.Benchmarks	success	✅

These checks are required after the changes to src/lightning/fabric/cli.py.

🟢 fabric: Docs

Check ID	Status
docs-make (fabric, doctest)	success	✅
docs-make (fabric, html)	success	✅

These checks are required after the changes to src/lightning/fabric/cli.py.

🟢 lightning_fabric: CPU workflow

Check ID	Status
fabric-cpu (macOS-14, lightning, 3.9, 2.1, oldest)	success	✅
fabric-cpu (macOS-14, lightning, 3.10, 2.1)	success	✅
fabric-cpu (macOS-14, lightning, 3.11, 2.2.2)	success	✅
fabric-cpu (macOS-14, lightning, 3.11, 2.3)	success	✅
fabric-cpu (macOS-14, lightning, 3.12.7, 2.4.1)	success	✅
fabric-cpu (macOS-14, lightning, 3.12.7, 2.5.1)	success	✅
fabric-cpu (ubuntu-20.04, lightning, 3.9, 2.1, oldest)	success	✅
fabric-cpu (ubuntu-20.04, lightning, 3.10, 2.1)	success	✅
fabric-cpu (ubuntu-20.04, lightning, 3.11, 2.2.2)	success	✅
fabric-cpu (ubuntu-20.04, lightning, 3.11, 2.3)	success	✅
fabric-cpu (ubuntu-22.04, lightning, 3.12.7, 2.4.1)	success	✅
fabric-cpu (ubuntu-22.04, lightning, 3.12.7, 2.5.1)	success	✅
fabric-cpu (windows-2022, lightning, 3.9, 2.1, oldest)	success	✅
fabric-cpu (windows-2022, lightning, 3.10, 2.1)	success	✅
fabric-cpu (windows-2022, lightning, 3.11, 2.2.2)	success	✅
fabric-cpu (windows-2022, lightning, 3.11, 2.3)	success	✅
fabric-cpu (windows-2022, lightning, 3.12.7, 2.4.1)	success	✅
fabric-cpu (windows-2022, lightning, 3.12.7, 2.5.1)	success	✅
fabric-cpu (macOS-14, fabric, 3.9, 2.1)	success	✅
fabric-cpu (ubuntu-20.04, fabric, 3.9, 2.1)	success	✅
fabric-cpu (windows-2022, fabric, 3.9, 2.1)	success	✅
fabric-cpu (macOS-14, fabric, 3.12.7, 2.5.1)	success	✅
fabric-cpu (ubuntu-22.04, fabric, 3.12.7, 2.5.1)	success	✅
fabric-cpu (windows-2022, fabric, 3.12.7, 2.5.1)	success	✅

These checks are required after the changes to src/lightning/fabric/cli.py, tests/tests_fabric/test_cli.py.

🟢 lightning_fabric: Azure GPU

Check ID	Status
lightning-fabric (GPUs) (testing Fabric | latest)	success	✅
lightning-fabric (GPUs) (testing Lightning | latest)	success	✅

These checks are required after the changes to src/lightning/__setup__.py, src/lightning/fabric/cli.py, tests/tests_fabric/test_cli.py.

🟢 mypy

Check ID	Status
mypy	success	✅

These checks are required after the changes to src/lightning/__setup__.py, src/lightning/fabric/cli.py.

🟢 install

Check ID	Status
install-pkg (ubuntu-22.04, fabric, 3.9)	success	✅
install-pkg (ubuntu-22.04, fabric, 3.11)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.9)	success	✅
install-pkg (ubuntu-22.04, pytorch, 3.11)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.9)	success	✅
install-pkg (ubuntu-22.04, lightning, 3.11)	success	✅
install-pkg (ubuntu-22.04, notset, 3.9)	success	✅
install-pkg (ubuntu-22.04, notset, 3.11)	success	✅
install-pkg (macOS-14, fabric, 3.9)	success	✅
install-pkg (macOS-14, fabric, 3.11)	success	✅
install-pkg (macOS-14, pytorch, 3.9)	success	✅
install-pkg (macOS-14, pytorch, 3.11)	success	✅
install-pkg (macOS-14, lightning, 3.9)	success	✅
install-pkg (macOS-14, lightning, 3.11)	success	✅
install-pkg (macOS-14, notset, 3.9)	success	✅
install-pkg (macOS-14, notset, 3.11)	success	✅
install-pkg (windows-2022, fabric, 3.9)	success	✅
install-pkg (windows-2022, fabric, 3.11)	success	✅
install-pkg (windows-2022, pytorch, 3.9)	success	✅
install-pkg (windows-2022, pytorch, 3.11)	success	✅
install-pkg (windows-2022, lightning, 3.9)	success	✅
install-pkg (windows-2022, lightning, 3.11)	success	✅
install-pkg (windows-2022, notset, 3.9)	success	✅
install-pkg (windows-2022, notset, 3.11)	success	✅

These checks are required after the changes to src/lightning/__setup__.py, src/lightning/fabric/cli.py.

---

Thank you for your contribution! 💜

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88%. Comparing base (d902516) to head (6bff2a8).
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #20588   +/-   ##
=======================================
  Coverage      88%      88%           
=======================================
  Files         267      267           
  Lines       23380    23369   -11     
=======================================
- Hits        20481    20478    -3     
+ Misses       2899     2891    -8