feat(web): add Brave Search (free tier) and DDGS search providers

Both implement WebSearchProvider via tools/web_providers/ — matching the
existing SearXNG pattern (PR #5c906d702). Search-only; pair with any
extract provider via web.extract_backend.

- tools/web_providers/brave_free.py — Brave Search API (free tier, 2k
  queries/mo). Uses BRAVE_SEARCH_API_KEY as X-Subscription-Token.
- tools/web_providers/ddgs.py — DuckDuckGo via the ddgs Python package.
  No API key; gated on package importability.
- tools/web_tools.py: both backends added to _get_backend() config list
  and auto-detect chain (trails paid providers), _is_backend_available,
  web_search_tool dispatch, web_extract_tool + web_crawl_tool search-only
  refusals, check_web_api_key, and the __main__ diagnostic. Introduces
  _ddgs_package_importable() helper so tests can monkeypatch a single
  symbol for the ddgs availability check.
- hermes_cli/tools_config.py: picker entries for both providers; ddgs
  gets a post_setup handler that runs `pip install ddgs`.
- hermes_cli/config.py: BRAVE_SEARCH_API_KEY in OPTIONAL_ENV_VARS.
- scripts/release.py: AUTHOR_MAP entry for @Abd0r.
- tests: 14 new tests (brave-free) + 15 new tests (ddgs) covering
  provider unit behavior, backend wiring, and search-only refusals.

Salvages the brave-free + ddgs portion of PR #19796. Not included: the
in-line helpers in web_tools.py (replaced with provider modules to match
the shipped architecture), the lynx-based extract path (these backends
should refuse extract with a clear error — users pair with a real
extract provider), and scripts/start-llama-server.sh (unrelated).

Co-authored-by: Abd0r <223003280+Abd0r@users.noreply.github.com>

hermes_cli/config.py

@@ -1864,6 +1864,14 @@ OPTIONAL_ENV_VARS = {
         "password": False,
         "category": "tool",
     },
+    "BRAVE_SEARCH_API_KEY": {
+        "description": "Brave Search API subscription token (free tier: 2,000 queries/mo)",
+        "prompt": "Brave Search subscription token",
+        "url": "https://brave.com/search/api/",
+        "tools": ["web_search"],
+        "password": True,
+        "category": "tool",
+    },
     "BROWSERBASE_API_KEY": {
         "description": "Browserbase API key for cloud browser (optional — local browser works without this)",
         "prompt": "Browserbase API key",

hermes_cli/tools_config.py

@@ -308,6 +308,23 @@ TOOL_CATEGORIES = {
                     {"key": "SEARXNG_URL", "prompt": "Your SearXNG instance URL (e.g., http://localhost:8080)", "url": "https://searxng.github.io/searxng/"},
                 ],
             },
+            {
+                "name": "Brave Search (Free Tier)",
+                "badge": "free tier · search only",
+                "tag": "2,000 queries/mo free — search only (pair with any extract provider)",
+                "web_backend": "brave-free",
+                "env_vars": [
+                    {"key": "BRAVE_SEARCH_API_KEY", "prompt": "Brave Search subscription token", "url": "https://brave.com/search/api/"},
+                ],
+            },
+            {
+                "name": "DuckDuckGo (ddgs)",
+                "badge": "free · no key · search only",
+                "tag": "Search via the ddgs Python package — no API key (pair with any extract provider)",
+                "web_backend": "ddgs",
+                "env_vars": [],
+                "post_setup": "ddgs",
+            },
         ],
     },
     "image_gen": {
@@ -669,6 +686,32 @@ def _run_post_setup(post_setup_key: str):
         _print_info("    Full voice list: https://github.com/OHF-Voice/piper1-gpl/blob/main/docs/VOICES.md")
         _print_info("    Switch voices by setting tts.piper.voice in ~/.hermes/config.yaml")
 
+    elif post_setup_key == "ddgs":
+        try:
+            __import__("ddgs")
+            _print_success("    ddgs is already installed")
+        except ImportError:
+            import subprocess
+            _print_info("    Installing ddgs (DuckDuckGo search package)...")
+            try:
+                result = subprocess.run(
+                    [sys.executable, "-m", "pip", "install", "-U", "ddgs", "--quiet"],
+                    capture_output=True, text=True, timeout=300,
+                )
+                if result.returncode == 0:
+                    _print_success("    ddgs installed")
+                else:
+                    _print_warning("    ddgs install failed:")
+                    _print_info(f"      {result.stderr.strip()[:300]}")
+                    _print_info("    Run manually: python -m pip install -U ddgs")
+                    return
+            except subprocess.TimeoutExpired:
+                _print_warning("    ddgs install timed out (>5min)")
+                _print_info("    Run manually: python -m pip install -U ddgs")
+                return
+        _print_info("    No API key required. DuckDuckGo enforces server-side rate limits.")
+        _print_info("    Pair with an extract provider if you also need web_extract.")
+
     elif post_setup_key == "spotify":
         # Run the full `hermes auth spotify` flow — if the user has no
         # client_id yet, this drops them into the interactive wizard