Filter out deleted items from graph relationships

[BenjaminCharmes]

Changes

• Modified get_graph_cy_format to filter out relationships pointing to non-existent/deleted items at the query level
• Prevents "nonexistent source" errors in the graph view without modifying the database

Question

• Deleted items are still present in synthesis_constituents and remain clickable (even if leading to errors). Should we handle this in the UI (disable links and/or different badge)?

[cypress]

datalab    Run #3957

Run Properties:   Passed #3957  •  d2d96946fc ℹ️: Merge 90841b9e2dae4fd9c7bfb5fee519e6292332d5e5 into 1a6d5e960c415f6c5e222fd99267...

Project	datalab
Branch Review	bc/filter-relationships
Run status	Passed #3957
Run duration	07m 22s
Commit	d2d96946fc ℹ️: Merge 90841b9e2dae4fd9c7bfb5fee519e6292332d5e5 into 1a6d5e960c415f6c5e222fd99267...
Committer	Ben Charmes
View all properties for this run ↗︎

---

Test results
Failures	0
Flaky	0
Pending	0
Skipped	0
Passing	336
View all changes introduced in this branch ↗︎

[codecov]

Codecov Report

❌ Patch coverage is 57.14286% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.03%. Comparing base (63105fc) to head (90841b9).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
pydatalab/src/pydatalab/routes/v0_1/graphs.py	57.14%	9 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1378      +/-   ##
==========================================
- Coverage   80.10%   80.03%   -0.07%     
==========================================
  Files          70       70              
  Lines        4759     4763       +4     
==========================================
  Hits         3812     3812              
- Misses        947      951       +4     

Files with missing lines	Coverage Δ
pydatalab/src/pydatalab/routes/v0_1/graphs.py	72.46% <57.14%> (-4.46%)	⬇️

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