fix(templates): search templates stop probing with searches; add firecrawl

Readiness probes ran real searches every interval: searxng's
searxng_web_search probe fanned a query out to every engine 1,440 times a
day, billing API-key engines (braveapi, kagi), and duckduckgo's `search`
probe scraped DuckDuckGo from the same IP agents search from.

- searxng: probe searxng_instance_info, which reads /config only
- duckduckgo: probe fetch_content on example.com every 300s
- firecrawl (new): firecrawl-mcp against a self-hosted or cloud
  Firecrawl, for reading pages as main-content markdown; probe
  firecrawl_scrape on example.com every 300s

Every probe still names a readiness tool, as templates.test.ts requires;
each was run against the real package before being written down.
docs/web-search.md now pairs searxng (search) with firecrawl (reading)
and says why duckduckgo does not hold up under agent traffic.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JPjtnE6Gd343oRNtMU9Bcd

README.md

@@ -869,17 +869,21 @@ Notes:
 
 ### Web search and docs lookup
 
-The `duckduckgo`, `searxng` and `docs-mcp` templates give an agent web search and
-version-pinned library documentation. All are self-hosted and none needs an API key.
-`duckduckgo` needs no backing service at all:
+The `searxng`, `firecrawl`, `duckduckgo` and `docs-mcp` templates give an agent web
+search, page reading and version-pinned library documentation. All can run
+self-hosted without an API key. For agents, pair `searxng` (search) with `firecrawl`
+(page reading); `duckduckgo` needs no backing service but scrapes from your IP and
+gets CAPTCHA-blocked under agent traffic:
 
 ```bash
-mcpctl create server websearch --from-template duckduckgo
+mcpctl create server searxng --from-template searxng --env SEARXNG_URL=http://searxng:8080
+mcpctl create server firecrawl --from-template firecrawl --env FIRECRAWL_API_URL=http://firecrawl-api:3002
 ```
 
 See [docs/web-search.md](docs/web-search.md) for the SearXNG engine setup (including
-the `json` format setting, without which every search silently returns nothing) and
-the `docs-mcp` index-persistence caveat.
+the `json` format setting, without which every search silently returns nothing), why
+none of the search templates probes with a search, and the `docs-mcp`
+index-persistence caveat.
 
 ## Gated Sessions