Fix cache swap issue

[YourRoyalLinus]

Description

Updated the get cache methods to return an empty cache if they do not find the keys they were expecting. This will lead to a cache miss in the calling function and the recreation of the cache, which is the intended behavior.

This will only occur the first time the LoadMode of the graph has been changed with caching is enabled.

I've added unit tests and completed local QA to confirm behavior.

Related Issue(s)

closes #2330

Breaking Change?

Checklist

• I have made corresponding changes to the documentation (if required)
• I have added tests that prove my fix is effective or that my feature works

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[Copilot]

Pull request overview

This PR fixes a cache invalidation bug that occurs when switching between LoadMode.DBT_LS and LoadMode.DBT_MANIFEST with caching enabled. The fix ensures that when a cache of the wrong type is encountered, an empty cache is returned to trigger a cache miss and force recreation of the correct cache type.

Changes:

• Modified get_dbt_ls_cache() and get_yaml_selectors_cache() to return empty dict when cache data is missing expected keys
• Added comprehensive unit tests to verify cache type mismatch handling
• Fixed documentation error that incorrectly referenced "dbt ls cache" in the YAML selectors cache section

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
cosmos/dbt/graph.py	Added else blocks to return empty dict when expected cache keys are missing, triggering proper cache misses
tests/dbt/test_graph.py	Added two new tests verifying that loading the wrong cache type results in a cache miss
docs/configuration/caching.rst	Corrected documentation to reference "yaml selectors cache" instead of "dbt ls cache" in the YAML selectors section

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.90%. Comparing base (98dc74b) to head (dbe9a33).
⚠️ Report is 8 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2332   +/-   ##
=======================================
  Coverage   97.90%   97.90%           
=======================================
  Files         102      102           
  Lines        6818     6820    +2     
=======================================
+ Hits         6675     6677    +2     
  Misses        143      143           

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[tatiana]

Thanks a lot, @YourRoyalLinus , for iterating and improving this feature further.