Pushforwards and pullbacks for everyone

[gdalle]

Core

• Implement pushforward based on pullback and pullback based on pushforward => if you forget both, you get a StackOverflowError
• Make derivative a simple pushforward of 1 and gradient a simple pullback of 1
• Replace traits ...Supported with ...Fast, because some backends may support pushforwards and pullbacks
• Replace functions supports_... with ..._performance

Tests

• Split testing from benchmarking
• Remove allocation tests
• Test all scenarios on pushforwards and pullbacks
• Add optional logging to test function instead of test file

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 96.12403% with 5 lines in your changes are missing coverage. Please review.

Project coverage is 93.13%. Comparing base (fb07d7f) to head (636b5e1).

Files	Patch %	Lines
src/traits.jl	90.90%	2 Missing ⚠️
.../DifferentiationInterfaceFastDifferentiationExt.jl	0.00%	1 Missing ⚠️
lib/DifferentiationInterfaceTest/src/tests/test.jl	92.30%	1 Missing ⚠️
src/backends.jl	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #113      +/-   ##
==========================================
- Coverage   93.77%   93.13%   -0.64%     
==========================================
  Files          55       56       +1     
  Lines        1414     1399      -15     
==========================================
- Hits         1326     1303      -23     
- Misses         88       96       +8     

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