- Add ExaWebSearchTool (web_search_exa) with keyword/semantic search,
category filters, domain restrictions, and date range support
- Add ExaGetContentsTool (exa_get_contents) for extracting web page content
- Add _exa_search() and _exa_get_contents() API helpers hitting
https://api.exa.ai/search and https://api.exa.ai/contents
- Add _EXA_KEY_ROTATOR for multi-key rotation
- Register Exa tools in _apply_web_search_tools() dispatch
- Add Exa to WEB_SEARCH_CITATION_TOOL_NAMES for citation support
- Add websearch_exa_key config default and provider option
- Add i18n metadata for en-US, zh-CN, ru-RU
- Add Exa section to docs (en + zh)
- Add 6 unit tests covering search, contents, error handling, and
legacy config migration
Closes#5621
* feat: add Firecrawl web search and extract tools, update configuration and tests
* feat: implement Firecrawl API integration and error handling in web search tools
* feat: enhance Firecrawl web search with session management and payload validation
* feat: Firecrawl web search to use aiohttp.ClientSession directly for improved session management as it was
* feat: update Firecrawl search to handle grouped web data response and add corresponding tests
* feat: refactor Firecrawl web search to use aiohttp.ClientSession for improved error handling and session management
* feat: remove unused coercion function and update Firecrawl search to use default limit in payload
