Refactor _default_freshness_callback to return list of (id, state) tuple

[pankajastro]

• Changed _default_freshness_callback return type from tuple[list[str], str] to list[tuple[str, str]] so each node carries its own state instead of
  sharing a single status string
• Renamed _skipped_node_token → _apply_node_state_tokens and _push_skipped_xcom_for_model → _push_node_state_xcom; both now accept an explicit state
  argument, enabling custom callbacks to push states other than "skipped"
• Nodes are added to self.exclude only when their state is "skipped"; other states push XCom but do not affect the dbt run
• Updated all call sites and tests; added a new test for the non-"skipped" state path

This set would set ground work for #2053

Related-to: #2053

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.05%. Comparing base (37fd06c) to head (fc38684).
⚠️ Report is 10 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2572   +/-   ##
=======================================
  Coverage   98.05%   98.05%           
=======================================
  Files         103      103           
  Lines        7601     7604    +3     
=======================================
+ Hits         7453     7456    +3     
  Misses        148      148           

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[Copilot]

Pull request overview

Refactors the WATCHER producer’s source-freshness “skip” callback to return per-node results as (unique_id, state) tuples instead of a (list[unique_id], state) pair, as groundwork for future source-node behavior improvements (Issue #2053).

Changes:

• Updated cosmos/operators/watcher.py:_default_freshness_callback return type to list[tuple[str, str]].
• Updated the producer call site to consume the new return shape.
• Updated _default_freshness_callback unit tests to assert against the new structure.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
cosmos/operators/watcher.py	Changes callback return type and adapts _apply_source_freshness to the new structure.
tests/operators/test_watcher.py	Updates tests to validate the new (unique_id, state) results.

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[tatiana]

Thanks, @pankajastro , it looks good, let's ship this as part of Cosmos 1.15.0