Add optional [search].base_url support for DuckDuckGo-compatible private search endpoints, including a preferred CODEWHALE_SEARCH_BASE_URL env override and the legacy DEEPSEEK_SEARCH_BASE_URL alias.
Network policy now gates the configured endpoint host, custom endpoints do not fall back to public Bing, non-DuckDuckGo provider/base_url combinations and challenge pages return explicit errors, and custom endpoint results report the configured host as their source.
Fixes#2436
Reported by @Artenx
Harvested from PR #2510 by @cyq1017
Co-authored-by: cyq1017 <61975706+cyq1017@users.noreply.github.com>
Hunter B
933637bb1c