test: add pool_config tests for socket_options

[Taure]

Summary

• Export pool_config/0 for testability
• 6 new tests covering socket_options behavior:
  • Default config values (no socket_options key)
  • Custom host/port/db/user/password/pool_size
  • [inet6] forwarded correctly
  • Multiple socket options [inet6, {recbuf, 8192}]
  • Empty list [] does not add socket_options key
  • Unset env does not add socket_options key

Covers the feature added in #82.

[github-actions]

🟢 Code Coverage — 93.5%

1921 of 2055 lines covered.

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🟡 ELP Lint — 1 warning

5 diagnostics found. See job logs for details.

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ℹ️ 11 OTP CVEs auto-ignored (already fixed in running version)

These CVEs are patched in the installed OTP version but NVD data
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CVE	Details
CVE-2026-23943	Fixed in 28.4.1, running 28.4.1 — Pre-auth SSH DoS via unbounded zlib inflate
CVE-2026-23942	Fixed in 28.4.1, running 28.4.1 — SFTP root escape via component-agnostic prefix check in ssh_sftpd
CVE-2026-23941	Fixed in 28.4.1, running 28.4.1 — Request smuggling via first-wins Content-Length parsing in inets httpd
CVE-2026-21620	Fixed in 28.3.2, running 28.4.1 — TFTP Path Traversal
CVE-2016-1000107	Fixed in 28.0.4, running 28.4.1 — Httpd CGI Scripts Environment Variable Pollution AKA "httpoxy"
CVE-2025-58050	Fixed in 28.0.3, running 28.4.1 — Buffer Read Overflow on Regular Expressions with (*scs:) and (*ACCEPT)
CVE-2025-48038	Fixed in 28.0.3, running 28.4.1 — SSH Unverified File Handles can Cause Excessive Use of System Resources
CVE-2025-48039	Fixed in 28.0.3, running 28.4.1 — SSH Unverified Paths can Cause Excessive Use of System Resources
CVE-2025-48040	Fixed in 28.0.3, running 28.4.1 — SSH Malicious Key Exchange Messages may Lead to Excessive Resource Consumption
CVE-2025-48041	Fixed in 28.0.3, running 28.4.1 — SSH_FXP_OPENDIR may Lead to Exhaustion of File Handles
CVE-2025-4748	Fixed in 28.0.1, running 28.4.1 — Absolute Path in Zip Module