Add SEMAPHORE_BUILD_INFO environment variable to override version display

[Copilot]

This PR adds support for the SEMAPHORE_BUILD_INFO environment variable to allow downstream Docker images to override the version string displayed in the Semaphore UI without rebuilding the binary.

Problem

When building downstream Docker images based on Semaphore (e.g., FROM semaphoreui/semaphore:v2.14.9), the UI continues to show the original version string like v2.14.9-66611eb-1746447063. Organizations want to display their own version information to users but previously had to rebuild the entire Semaphore binary to achieve this.

Solution

Modified the Version() function in util/version.go to check for the SEMAPHORE_BUILD_INFO environment variable:

• If set and non-empty, returns the custom version string
• If not set or empty, falls back to the default {Ver}-{Commit}-{Date} format
• Works across all contexts: CLI commands, API endpoints, and frontend display

Usage Examples

Docker runtime override:

docker run -e SEMAPHORE_BUILD_INFO="v2.14.9-mycompany-1.0.0" semaphoreui/semaphore:v2.14.9

Dockerfile for downstream builds:

FROM semaphoreui/semaphore:v2.14.9
ENV SEMAPHORE_BUILD_INFO="v2.14.9-downstream-custom"

Testing

• Added comprehensive unit tests covering all scenarios
• Created API integration test to verify endpoint behavior
• Verified CLI semaphore version command works correctly
• Confirmed frontend displays the first part of custom versions in Docker commands
• All existing tests continue to pass

Backward Compatibility

The change is fully backward compatible - existing installations continue to work unchanged, and the new feature is only activated when the environment variable is explicitly set.

Fixes #3237.

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.