ci: adopt canonical l9-ci-core pipeline

[cryptoxdog]

Adopt the canonical l9-ci-core reusable pipeline via a thin caller at .github/workflows/ci.yml.

Generated by the l9-repo-preflight CI-changeover on an isolated branch — never pushed to main directly.

• action: create (no prior .github/workflows/ci.yml)
• reusable_ref: Quantum-L9/l9-ci-core/.github/workflows/pr-pipeline.yml@102c9a5960c53c607216d320339e0457046948cb
• triggers: pull_request + push on main, plus workflow_dispatch
• secrets: inherit
• local validation: passed (YAML parses, exact-SHA pin, secrets inherit, targets main)

Note: this caller references Quantum-L9/l9-ci-core at the pinned SHA. Confirm that repo/SHA is reachable to the workflow before merging, otherwise the CI check will fail to resolve the reusable workflow.

🤖 Generated with Claude Code

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Generated by Claude Code

[sonarqubecloud]

Quality Gate failed

Failed conditions
C Security Rating on New Code (required ≥ A)

See analysis details on SonarQube Cloud

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