Add Azure Pipelines for cross-platform CI verification (macOS, Windows, Linux)

[rmems]

Summary

Add an Azure Pipelines configuration to run CPU-only cross-platform verification on ubuntu-latest, macos-latest, and windows-latest alongside the existing GitHub Actions workflow (.github/workflows/ci.yml).

Motivation

The repository currently validates builds and tests exclusively through GitHub Actions on ubuntu-latest only (basic fmt/clippy/build/test with pinned actions and caching). Running the same CPU checks on Azure Pipelines provides:

• Cross-platform coverage for macOS and Windows (critical for a pure-Rust, zero-dependency crate that should behave identically everywhere).
• A redundant CI signal in case GitHub Actions has outages or runner issues.
• Early detection of platform-specific build/test regressions (e.g., path separators, case sensitivity, linking, line endings).

This follows the exact pattern established in the sibling rmems/corinth-canal repo (open issue #109) for org consistency across Limen-Neural Rust libraries.

Scope

Run the following CPU-only checks on every pull request and push to main:

• cargo fmt --check
• cargo clippy --all-targets --all-features -- -D warnings (adapt dead_code allowance if any in engram surface)
• cargo test --all-features (or --lib --locked for speed)
• cargo check --examples --all-features --locked (or build)
• Optional: cargo llvm-cov --lib --all-features --locked --lcov --output-path lcov.info (follow-up if coverage desired)

Platforms:

• ubuntu-latest
• macos-latest
• windows-latest

Toolchain: latest stable Rust via rustup default stable.

The azure-pipelines.yml should live at the repository root (matching corinth-canal convention).

Non-goals

• GPU/CUDA or self-hosted runners (n/a for this pure CPU zero-dep crate; those remain on GitHub Actions if ever added).
• Docker build/publish remains (or will be) on GitHub Actions (see sibling Docker issue).
• Sentry release workflow (not used here).
• Making the Azure check required immediately (start as informational, per corinth #109 open questions).

Acceptance Criteria

• azure-pipelines.yml exists at the repository root.
• Pipeline triggers on pull requests and pushes to main.
• Linux, macOS, and Windows jobs all run fmt, clippy, build/check, and test steps with caching.
• Clippy warnings fail the build, matching GitHub Actions behavior.
• Azure Pipelines check appears on pull requests (informational to start).
• Coverage upload to Codecov is configured or a follow-up issue is filed (if llvm-cov step added).
• Documentation (README.md) mentions the new pipeline in a ## Development or CI section (with commands + links to both GH + Azure).
• Cross-link to the sibling Docker workflow issue.

Open Questions

• Should Azure Pipelines upload LCOV coverage to Codecov to mirror GitHub Actions (if coverage step is added)?
• Should the Azure Pipelines check be required for merge, or start as informational?
• Which Azure Pipelines caching strategy should be used for Cargo registry and target/ (matching the existing GH ci.yml cache key)?
• Any org-level Azure DevOps project/secret setup required beyond the yml?

Related

• .github/workflows/ci.yml (current GH Actions)
• corinth-canal #109 (Azure template we are mirroring)
• (Sibling) Docker workflow issue (to be created in same batch)
• Prior engram issues Add GitHub Actions CI workflow for code validation #2 (original GH Actions), docs: produce engram-parser role in boundary matrix (LIM-9) + publish prep #4/Define MoE extraction traits inside this crate #5/parser: adopt/enhance as canonical GGUF parser by extracting from corinth-canal #7 (DX/modularization)
• LIM-9 (boundary matrix)

---

Modeled after corinth-canal #109 and engram's existing CI patterns for org consistency.

[rmems]

Sibling issue (Docker workflow): #9

Both follow the pattern from corinth-canal #109 (Azure) and its docker-build.yml for org consistency. See plan for details.

[rmems]

New CI/CD improvement issues created (better GH + security + releases + MSRV + dependabot + layout hygiene, per approved plan). Cross-links:

• ci: harden and enhance GitHub Actions workflow (adopt corinth-canal patterns: pinned SHAs, rust-cache, llvm-cov + Codecov, schedule, concurrency) #11 harden/enhance GH Actions (pinned SHAs, coverage with Codecov, etc.)
• ci: add security scanning workflow (RustSec audit + Snyk SCA/SAST with SARIF, modeled on corinth-canal) #12 security scanning (RustSec + Snyk)
• ci: add GitHub Releases on tags (can use sentry; no automated crates.io release) #13 GH releases on tags (sentry possible; no crates.io auto)
• ci: establish Minimum Supported Rust Version (MSRV) policy and test it in CI #14 MSRV policy + CI test
• repo: add Dependabot for GitHub Actions and future dependencies #15 Dependabot (no auto-merge)
• repo: clean up duplicated source layout and publish artifacts (engram-parser/ nested dir) #16 layout clean (nested dir etc.)

See #9 (Docker) too. All build on the existing CI baseline + corinth/neuromod patterns for Limen-Neural DX (LIM-9). Grok Build assisted drafting.