fix: replace MissingBackendError with error hint

[gdalle]

The exception we used to throw was hiding the real cause of the error. Now we leave the original MethodError but add an error hint in bold underneath:

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.51%. Comparing base (881fc3f) to head (d4f7074).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #656      +/-   ##
==========================================
- Coverage   97.53%   97.51%   -0.03%     
==========================================
  Files         112      111       -1     
  Lines        5561     5546      -15     
==========================================
- Hits         5424     5408      -16     
- Misses        137      138       +1     

Flag	Coverage Δ
DI	98.62% <100.00%> (-0.04%)	⬇️
DIT	95.36% <ø> (ø)

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