Update Catalyst to use the toml module in PennyLane

[astralcai]

Context:

This PR is part of the new device capabilities initiative to improve feature parity between PennyLane and Catalyst. See this ADR for more context. A new TOML schema has been defined, and the relevant module implemented in PennyLane:

• [New Device Capabilities] Implement the DeviceCapabilities data class and the TOML module. pennylane#6407
• [New Device Capabilities] Add capabilities to the device API pennylane#6433.

Description of the Change:

• Removes the toml module and replaces all usages with imports from PennyLane
• Update usages of DeviceCapabilities to match the new definition in [New Device Capabilities] Implement the DeviceCapabilities data class and the TOML module. pennylane#6407
• Removes use of about-to-be-deprecated return_type of MPs
• Updates all TOML files to use the new schema.
• A PR opened in Lightning Update Lightning device TOML files to the new schema pennylane-lightning#988 that updates the TOML file of the Lightning devices to the new schema.

Benefits:

A step towards feature parity between PennyLane and Catalyst.

Possible Drawbacks:

• Per discussions when the ADR was developed, operator.gates.decomp and operator.gates.matrix are removed, and the TOML file no longer prescribes to the framework how an operator should be handled. This will change the behaviour of decomposition for some circuits.

Related GitHub Issues:

[sc-71888]
[sc-71728]
[sc-71730]

[github-actions]

Hello. You may have forgotten to update the changelog!
Please edit doc/releases/changelog-dev.md on your branch with:

• A one-to-two sentence description of the change. You may include a small working example for new features.
• A link back to this PR.
• Your name (or GitHub username) in the contributors section.

[astralcai]

TODO: revert these before merge

[codecov]

Codecov Report

Attention: Patch coverage is 92.85714% with 6 lines in your changes missing coverage. Please review.

Project coverage is 97.92%. Comparing base (54df305) to head (9d8b763).

Files with missing lines	Patch %	Lines
frontend/catalyst/device/verification.py	86.36%	2 Missing and 1 partial ⚠️
frontend/catalyst/device/decomposition.py	90.47%	1 Missing and 1 partial ⚠️
frontend/catalyst/device/qjit_device.py	96.66%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1275      +/-   ##
==========================================
- Coverage   97.95%   97.92%   -0.04%     
==========================================
  Files          77       76       -1     
  Lines       11321    11222      -99     
  Branches      982      972      -10     
==========================================
- Hits        11090    10989     -101     
- Misses        181      182       +1     
- Partials       50       51       +1     

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