fix: enable SDK skill auto-discovery and unify skill directories

The Claude Agent SDK backend was not loading skills because
`setting_sources` and the `Skill` tool were missing from the options
passed to `ClaudeAgentOptions`.

- Add `setting_sources=["user", "project"]` so the SDK discovers
  SKILL.md files from `~/.claude/skills/` and `.claude/skills/`
- Add `"Skill"` to `allowed_tools` and the `_SDK_TO_POLICY` mapping
- Add `"skill"` to `group:skills` in the policy system
- Add `~/.claude/skills/` to SkillLoader search paths
- Write agent-created skills to `~/.claude/skills/` (SDK-standard
  location) instead of `~/.pocketpaw/skills/`

Closes #177

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/pocketpaw/agents/claude_sdk.py

@@ -170,6 +170,7 @@ class ClaudeAgentSDK:
         "Grep": "shell",  # search is shell-adjacent
         "WebSearch": "browser",
         "WebFetch": "browser",
+        "Skill": "skill",
     }
 
     def __init__(self, settings: Settings, executor: ExecutorProtocol | None = None):
@@ -739,6 +740,7 @@ class ClaudeAgentSDK:
                 "Grep",
                 "WebSearch",
                 "WebFetch",
+                "Skill",
             ]
             allowed_tools = [
                 t
@@ -763,6 +765,7 @@ class ClaudeAgentSDK:
             options_kwargs = {
                 "system_prompt": final_prompt,
                 "allowed_tools": allowed_tools,
+                "setting_sources": ["user", "project"],
                 "hooks": hooks,
                 "cwd": str(self._cwd),
                 "max_turns": 25,  # Safety net against runaway tool loops

src/pocketpaw/skills/loader.py

@@ -22,6 +22,7 @@ logger = logging.getLogger(__name__)
 # Skill search paths in priority order (later overrides earlier)
 SKILL_PATHS = [
     Path.home() / ".agents" / "skills",  # From skills.sh (central)
+    Path.home() / ".claude" / "skills",  # Claude Code / SDK standard
     Path.home() / ".pocketpaw" / "skills",  # PocketPaw-specific
 ]
 

src/pocketpaw/tools/builtin/skill_gen.py

@@ -14,8 +14,13 @@ logger = logging.getLogger(__name__)
 
 
 def _get_skills_dir() -> Path:
-    """Get (and create) the PocketPaw skills directory."""
-    d = get_config_dir() / "skills"
+    """Get (and create) the user skills directory.
+
+    Writes to ``~/.claude/skills/`` — the standard location used by the
+    Claude Agent SDK for auto-discovery.  PocketPaw's SkillLoader also
+    scans this directory so skills are available in both systems.
+    """
+    d = Path.home() / ".claude" / "skills"
     d.mkdir(parents=True, exist_ok=True)
     return d
 

src/pocketpaw/tools/policy.py

@@ -28,7 +28,7 @@ TOOL_GROUPS: dict[str, list[str]] = {
     "group:memory": ["remember", "recall", "forget"],
     "group:desktop": ["desktop"],
     "group:search": ["web_search", "url_extract"],
-    "group:skills": ["create_skill"],
+    "group:skills": ["create_skill", "skill"],
     "group:gmail": ["gmail_search", "gmail_read", "gmail_send"],
     "group:calendar": ["calendar_list", "calendar_create", "calendar_prep"],
     "group:voice": ["text_to_speech", "speech_to_text"],