fix: align Go version across CI workflows with go.mod

[Rayhan1967]

Summary

This PR resolves the Go version inconsistency between the go.mod file and CI workflow configurations.

Problem

The project specifies go 1.25.6 in go.mod, but the CI workflows were using:

• 1.25.5 in main.yaml, pr.yaml, and e2e.yaml
• stable in golangci-lint.yaml

This version mismatch can lead to inconsistent build environments and potential CI failures.

Solution

Updated all GitHub Actions workflow files to use Go version 1.25.6:

Workflow File	Updated Version
.github/workflows/main.yaml	1.25.6
.github/workflows/pr.yaml	1.25.6
.github/workflows/e2e.yaml	1.25.6
.github/workflows/golangci-lint.yaml	1.25.6

Verification

All checks passed:

• ✅ golangci-lint run ./... - 0 issues
• ✅ go test -short ./... - All tests pass
• ✅ go build - Build successful

Checklist

• Code follows project conventions
• Tests pass locally
• Linting passes