ci: add PR CI

[arad-starkware]

Note

Adds a PR GitHub Actions workflow running flow verification, tests with coverage upload, and formatting checks; adjusts flow-check script path and enables dev Cairo debug profile.

• CI (GitHub Actions):
  • Adds on-pull-request.yaml with jobs:
    • verify_flows: sets up Python and runs scripts/check_all_flows_have_test.py --allow-duplicate-tests.
    • test: sets up Starknet Foundry 0.49.0, Scarb 2.12.2, installs cairo-coverage, runs scarb test -w --coverage, uploads coverage.lcov to Codecov, and checks formatting via scarb fmt -w --check.
• Scripts:
  • Updates scripts/check_all_flows_have_test.py to fix CONTRACTS_FOLDER path resolution.
• Contracts config:
  • Updates workspace/apps/staking/contracts/Scarb.toml with [profile.dev.cairo] enabling debug info and setting inlining-strategy = "avoid".

^{Written by Cursor Bugbot for commit 45cee2c. This will update automatically on new commits. Configure here.}

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[codecov]

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[arad-starkware]

• chore: remove workspace, change to single package repo #25
• ci: add PR CI #24 👈 (View in Graphite)
• main

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[noa-starkware]

Reviewable status: 0 of 3 files reviewed, all discussions resolved (waiting on @NirLevi-starkware)