feat(web): add Parallel as alternative web search/extract backend (#1696)

* feat(web): add Parallel as alternative web search/extract backend

Adds Parallel (parallel.ai) as a drop-in alternative to Firecrawl for
web_search and web_extract tools using the official parallel-web SDK.

- Backend selection via WEB_SEARCH_BACKEND env var (auto/parallel/firecrawl)
- Auto mode prefers Firecrawl when both keys present; Parallel when sole backend
- web_crawl remains Firecrawl-only with clear error when unavailable
- Lazy SDK imports, interrupt support, singleton clients
- 16 new unit tests for backend selection and client config

Co-authored-by: s-jag <s-jag@users.noreply.github.com>

* fix: add PARALLEL_API_KEY to config registry and fix web_crawl policy tests

Follow-up for Parallel backend integration:
- Add PARALLEL_API_KEY to OPTIONAL_ENV_VARS (hermes doctor, env blocklist)
- Add to set_config_value api_keys list (hermes config set)
- Add to doctor keys display
- Fix 2 web_crawl policy tests that didn't set FIRECRAWL_API_KEY
  (needed now that web_crawl has a Firecrawl availability guard)

* refactor: explicit backend selection via hermes tools, not auto-detect

Replace the auto-detect backend selection with explicit user choice:
- hermes tools saves WEB_SEARCH_BACKEND to .env when user picks a provider
- _get_backend() reads the explicit choice first
- Fallback only for manual/legacy config (uses whichever key is present)
- _is_provider_active() shows [active] for the selected web backend
- Updated tests, docs, and .env.example to remove 'auto' mode language

* refactor: use config.yaml for web backend, not env var

Match the TTS/browser pattern — web.backend is stored in config.yaml
(set by hermes tools), not as a WEB_SEARCH_BACKEND env var.

- _load_web_config() reads web: section from config.yaml
- _get_backend() reads web.backend from config, falls back to key detection
- _configure_provider() saves to config dict (saved to config.yaml)
- _is_provider_active() reads from config dict
- Removed WEB_SEARCH_BACKEND from .env.example, set_config_value, docs
- Updated all tests to mock _load_web_config instead of env vars

---------

Co-authored-by: s-jag <s-jag@users.noreply.github.com>

hermes_cli/tools_config.py

@@ -151,19 +151,29 @@ TOOL_CATEGORIES = {
     "web": {
         "name": "Web Search & Extract",
         "setup_title": "Select Search Provider",
-        "setup_note": "A free DuckDuckGo search skill is also included — skip this if you don't need Firecrawl.",
+        "setup_note": "A free DuckDuckGo search skill is also included — skip this if you don't need a premium provider.",
         "icon": "🔍",
         "providers": [
             {
                 "name": "Firecrawl Cloud",
-                "tag": "Recommended - hosted service",
+                "tag": "Hosted service - search, extract, and crawl",
+                "web_backend": "firecrawl",
                 "env_vars": [
                     {"key": "FIRECRAWL_API_KEY", "prompt": "Firecrawl API key", "url": "https://firecrawl.dev"},
                 ],
             },
+            {
+                "name": "Parallel",
+                "tag": "AI-native search and extract",
+                "web_backend": "parallel",
+                "env_vars": [
+                    {"key": "PARALLEL_API_KEY", "prompt": "Parallel API key", "url": "https://parallel.ai"},
+                ],
+            },
             {
                 "name": "Firecrawl Self-Hosted",
                 "tag": "Free - run your own instance",
+                "web_backend": "firecrawl",
                 "env_vars": [
                     {"key": "FIRECRAWL_API_URL", "prompt": "Your Firecrawl instance URL (e.g., http://localhost:3002)"},
                 ],
@@ -618,6 +628,9 @@ def _is_provider_active(provider: dict, config: dict) -> bool:
     if "browser_provider" in provider:
         current = config.get("browser", {}).get("cloud_provider")
         return provider["browser_provider"] == current
+    if provider.get("web_backend"):
+        current = config.get("web", {}).get("backend")
+        return current == provider["web_backend"]
     return False
 
 
@@ -650,6 +663,11 @@ def _configure_provider(provider: dict, config: dict):
         else:
             config.get("browser", {}).pop("cloud_provider", None)
 
+    # Set web search backend in config if applicable
+    if provider.get("web_backend"):
+        config.setdefault("web", {})["backend"] = provider["web_backend"]
+        _print_success(f"  Web backend set to: {provider['web_backend']}")
+
     if not env_vars:
         _print_success(f"  {provider['name']} - no configuration needed!")
         return