Update Go to 1.25.3 and Alpine to 3.21.3 to address security vulnerab…

[vikram-avesha]

🔒 Security: Update Go and Alpine versions to address vulnerabilities

Changes

• Updated Go from 1.22.5 → 1.25.3
• Updated Alpine from 3.20.1 → 3.21.3
• Updated go.mod directive from go 1.18 → go 1.25

Impact

• Addresses 12 Alpine vulnerabilities (including 4 HIGH severity OpenSSL issues)
• Addresses 22+ Go stdlib HIGH severity vulnerabilities
• No dependency version changes required

Trivy Scan Results (Before)

• Alpine: 12 vulnerabilities (8 MEDIUM, 4 HIGH)
• Go Binary (stdlib 1.22.5): 22 vulnerabilities (16 MEDIUM, 6 HIGH)
• Multiple CVEs in OpenSSL (libcrypto3, libssl3)
• Critical Go stdlib issues (CVE-2025-58183, CVE-2025-58186, etc.)

Expected significant vulnerability reduction after this update.