Generalize site search for all registered sources and normalize result URLs

[kmatsunami]

Motivation

• Expand the search capability to cover all registered sources instead of the previous two hard-coded sources.
• Unify duplicate per-site search logic into a single generic extractor to simplify maintenance and add per-source configuration.
• Ensure discovered result URLs are resolved, domain-checked, and canonicalized to existing seed URL normalization logic.

Description

• Replaced hard-coded SUPPORTED_SEARCH_SOURCES with REGISTERED_SOURCES and imported normalize_seed_url from manga_watch.sources and switched quote to quote_plus for query encoding.
• Added _SOURCE_SEARCH_CONFIG to declare each source's search_url and allowed_domains and implemented _search_via_public_site to drive searches for any configured source.
• Reworked anchor parsing into _extract_anchor_results and added helpers _resolve_result_url, _is_allowed_domain, and _canonical_seed_url_for_source to resolve relative links, enforce allowed domains, and produce canonical seed URLs via normalize_seed_url.
• Removed source-specific search functions and _normalize_result_url, and built _SEARCHERS dynamically so each registered source uses the generic search path.

Testing

• Ran updated unit tests in tests/test_source_search.py which assert supported sources and seed URL normalization and they passed.
• Ran tests/test_discord_command_registration_search.py which validates the expanded search choices and it passed.
• Ran tests/test_discord_supertwins.py which checks search invocation behavior and it passed.

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Codex Task

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Bound synchronous source fan-out to avoid command timeouts

Making SUPPORTED_SEARCH_SOURCES equal to every registered adapter means supertwins search now fans out synchronously across up to 13 non-root sources (_search_results loops sources one-by-one and each call does blocking HTTP). With the current HTTP defaults (25s timeout and retries), one slow/unreachable site can stall a source search for a long time, so a single interaction can exceed Discord response windows by minutes. This regression is introduced by expanding the source list without adding parallelism or tighter fail-fast behavior.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Resolve all relative href forms before URL validation

_resolve_result_url currently resolves only root-relative links (/path) and drops document-relative links like works/123, ./episode/..., or ../series/... because they reach urlsplit without a scheme and are rejected. That means valid anchors can silently disappear from results on sites that emit non-root relative URLs. The previous implementation used urljoin for all hrefs, so this is a behavior regression in link extraction.

Useful? React with 👍 / 👎.