[Ultroncn]

Related issue

Part of #40372

Summary

Dataset.available_segment_count is the last @property in api/models/dataset.py that reads from the global db.session. This PR replaces it with an explicit-session method, matching the get_* convention already used by all its neighbors.

• Removes the @property decorator and renames to get_available_segment_count(self, *, session: Session) -> int.
• Passes the caller-provided session to session.scalar(...) instead of db.session.scalar(...).
• Updates the existing container integration test to call the method with session=db_session_with_containers.

This is a narrowly scoped, non-overlapping slice. available_segment_count has exactly two references in the repository: its definition and the integration test. No other open PR touches this symbol. The neighboring refactor PR #41647 explicitly leaves this symbol out of scope.

Scope and compatibility

• No production callers exist outside the test file.
• The query, filter conditions, and return type are unchanged.

Verification

• Updated test passes with the new method signature.
• No other test references available_segment_count.
• Ruff lint and format check pass on the two changed files.

From Claude Code

🤖 Generated with Claude Code

[github-actions]

Pyrefly Type Coverage

Metric	Base	PR	Delta
Type coverage	65.12%	65.12%	+0.00%
Strict coverage	64.73%	64.73%	+0.00%
Typed symbols	47,503	47,505	+2
Untyped symbols	25,596	25,595	-1
Modules	3430	3430	0

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.58%. Comparing base (9a0961a) to head (bbad351).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #42523   +/-   ##
=======================================
  Coverage   87.58%   87.58%           
=======================================
  Files        5471     5471           
  Lines      318391   318384    -7     
  Branches    63816    63813    -3     
=======================================
- Hits       278871   278866    -5     
+ Misses      34129    34127    -2     
  Partials     5391     5391           

Flag	Coverage Δ
api	87.27% <100.00%> (+<0.01%)	⬆️

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