Bump compat to TensorKit v0.16 + deprecate old projection methods

[lkdvos]

This PR bumps the TensorKit compat to v0.16, and uses the new MatrixAlgebraKit projections instead of the ones defined here.
I think I managed to keep everything non-breaking by deprecating the old projection schemes, so I only bumped the patch version.

[codecov]

Codecov Report

❌ Patch coverage is 93.33333% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 72.57%. Comparing base (0238f05) to head (05667de).
⚠️ Report is 4 commits behind head on master.

Files with missing lines	Patch %	Lines
src/stiefel.jl	83.33%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #19      +/-   ##
==========================================
- Coverage   74.28%   72.57%   -1.71%     
==========================================
  Files           5        5              
  Lines         591      485     -106     
==========================================
- Hits          439      352      -87     
+ Misses        152      133      -19     

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