Remove dispensable C++ source code in Lightning wheels

[maliasadi]

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---

Context:
Remove dispensable C++ source code in Lightning wheels. 🚧 Testing is still in progress! 🚧

Description of the Change:

• Remove core src files in Lightning wheels

Benefits:

• Fix the issue with installing PennyLane with Lightning-Qubit on older versions of Windows that has a maximum limit on the length of file paths.
• Cleaner wheels src directory by removing unneeded C++ src code.

Possible Drawbacks:

Related GitHub Issues:
[sc-82977]
[sc-82978]

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 27.80%. Comparing base (2878283) to head (b2168d6).

❗ There is a different number of reports uploaded between BASE (2878283) and HEAD (b2168d6). Click for more details.

HEAD has 4 uploads less than BASE

Flag	BASE (2878283)	HEAD (b2168d6)
	8	4

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #1098       +/-   ##
===========================================
- Coverage   96.07%   27.80%   -68.28%     
===========================================
  Files         235       28      -207     
  Lines       39745     2658    -37087     
===========================================
- Hits        38186      739    -37447     
- Misses       1559     1919      +360     

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