Add EL7 (CentOS 7) CI/CD support for i686 and x86_64

[Copilot]

Extends CI/CD coverage to Enterprise Linux 7 with RPM packaging for both x86_64 and i686, matching the existing EL6 pattern.

New files

• build/SPECS/cnee-el7.spec — RPM spec for EL7; uses GPLv3+ licence tag and plain make/make install DESTDIR= (EL7-compatible macros)
• .github/workflows/el7.yml — GHA workflow with arch: [x86_64, i686] matrix

Workflow design

Follows the EL6 approach exactly: runs on ubuntu-latest and shells into centos:7 via explicit docker run (avoids Node 20 requiring glibc ≥ 2.17 vs the container directive injecting the runner into the image).

CentOS 7 is EOL, so repos are redirected to vault.centos.org/7.9.2009.

i686 builds use the same gcc -m32 wrapper strategy as EL6:

printf '#!/bin/sh\nexec gcc -m32 "$@"\n' > /usr/local/bin/i686-redhat-linux-gnu-gcc
# rpmbuild driven via:
rpmbuild -ba \
    --define "_host i686-redhat-linux-gnu" \
    --define "_target_cpu i686" \
    --define "optflags -O2 -g -m32 -march=i686 -mtune=generic" \
    "$HOME/rpmbuild/SPECS/cnee.spec"

Artifacts are uploaded as cnee-el7-x86_64-rpm and cnee-el7-i686-rpm.

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.

[Copilot]

Pull request overview

Adds GitHub Actions CI/CD coverage for Enterprise Linux 7 (CentOS 7.9 vault) and produces RPM artifacts for both x86_64 and i686, mirroring the existing EL6 workflow pattern.

Changes:

• Introduce an EL7 RPM spec (build/SPECS/cnee-el7.spec) aligned with the existing EL6 spec approach.
• Add an EL7 GitHub Actions workflow (.github/workflows/el7.yml) that builds/tests in centos:7 via docker run, with an x86_64/i686 matrix and RPM artifact upload.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
build/SPECS/cnee-el7.spec	Adds an EL7-focused RPM spec for packaging cnee using EL7-compatible build/install macros.
.github/workflows/el7.yml	Adds an EL7 CI workflow that builds, runs the existing e2e script, and produces RPM/SRPM artifacts for both architectures.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.