fix(graphql): Re-add deprecated coverage totals fields for backward compatibility

[sentry]

This PR addresses issue API-EC9, a GraphQLError: Cannot query field 'lines' on type 'CoverageTotals'.

Root Cause:
The CoverageTotals GraphQL type had its lines, hits, and misses fields renamed to lineCount, hitsCount, and missesCount respectively. The old field names were removed from the schema without deprecated aliases, causing a breaking change for clients still querying the old field names.

Solution:
This PR re-introduces the lines, hits, and misses fields to the CoverageTotals GraphQL type, marking them as @deprecated and pointing to their new lineCount, hitsCount, and missesCount counterparts. Additionally, identity aliases are added in the Python coverage_totals.py file to ensure Ariadne correctly resolves these deprecated fields from the underlying data object attributes.

This change restores backward compatibility for existing clients using the old field names, while new clients are encouraged to use the updated field names.

Legal Boilerplate

Look, I get it. The entity doing business as "Sentry" was incorporated in the State of Delaware in 2015 as Functional Software, Inc. In 2022 this entity acquired Codecov and as result Sentry is going to need some rights from me in order to utilize my contributions in this PR. So here's the deal: I retain all rights, title and interest in and to my contributions, and by keeping this boilerplate intact I confirm that Sentry can use, modify, copy, and redistribute my contributions, under Sentry's choice of terms.

Fixes API-EC9

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.89%. Comparing base (7b60783) to head (2b8873b).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1204   +/-   ##
=======================================
  Coverage   91.89%   91.89%           
=======================================
  Files        1325     1325           
  Lines       50862    50865    +3     
  Branches     1626     1626           
=======================================
+ Hits        46741    46744    +3     
  Misses       3815     3815           
  Partials      306      306           

Flag	Coverage Δ
apiunit	94.95% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

[codecov-notifications]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ All tests successful. No failed tests found.

📢 Thoughts on this report? Let us know!

🚀 New features to boost your workflow:

• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.