feat: enhancement workflow preset system with multi-target CLI

- Add YAML-based enhancement workflow presets shipped inside the package
  (default, minimal, security-focus, architecture-comprehensive, api-documentation)
- Add `skill-seekers workflows` subcommand: list, show, copy, add, remove, validate
- copy/add/remove all accept multiple names/files in one invocation with partial-failure behaviour
- `add --name` override restricted to single-file operations
- Add 5 MCP tools: list_workflows, get_workflow, create_workflow, update_workflow, delete_workflow
- Fix: create command _add_common_args() now correctly forwards each --enhance-workflow
  as a separate flag instead of passing the whole list as a single argument
- Update README: reposition as "data layer for AI systems" with AI Skills front and centre
- Update CHANGELOG, QUICK_REFERENCE, CLAUDE.md with workflow preset details
- 1,880+ tests passing

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/skill_seekers/mcp/server_fastmcp.py

@@ -103,6 +103,12 @@ try:
         submit_config_impl,
         upload_skill_impl,
         validate_config_impl,
+        # Workflow tools
+        list_workflows_impl,
+        get_workflow_impl,
+        create_workflow_impl,
+        update_workflow_impl,
+        delete_workflow_impl,
     )
 except ImportError:
     # Fallback for direct script execution
@@ -137,6 +143,11 @@ except ImportError:
         submit_config_impl,
         upload_skill_impl,
         validate_config_impl,
+        list_workflows_impl,
+        get_workflow_impl,
+        create_workflow_impl,
+        update_workflow_impl,
+        delete_workflow_impl,
     )
 
 # Initialize FastMCP server
@@ -1178,6 +1189,100 @@ async def export_to_qdrant(
     return str(result)
 
 
+# ============================================================================
+# WORKFLOW TOOLS (5 tools)
+# ============================================================================
+
+
+@safe_tool_decorator(
+    description="List all available enhancement workflows (bundled defaults + user-created). Returns name, description, and source (bundled/user) for each."
+)
+async def list_workflows() -> str:
+    """List all available enhancement workflow presets."""
+    result = list_workflows_impl({})
+    if isinstance(result, list) and result:
+        return result[0].text if hasattr(result[0], "text") else str(result[0])
+    return str(result)
+
+
+@safe_tool_decorator(
+    description="Get the full YAML content of a named enhancement workflow. Searches user dir first, then bundled defaults."
+)
+async def get_workflow(name: str) -> str:
+    """
+    Get full YAML content of a workflow.
+
+    Args:
+        name: Workflow name (e.g. 'security-focus', 'default')
+
+    Returns:
+        YAML content of the workflow, or error message if not found.
+    """
+    result = get_workflow_impl({"name": name})
+    if isinstance(result, list) and result:
+        return result[0].text if hasattr(result[0], "text") else str(result[0])
+    return str(result)
+
+
+@safe_tool_decorator(
+    description="Create a new user workflow from YAML content. The workflow is saved to ~/.config/skill-seekers/workflows/."
+)
+async def create_workflow(name: str, content: str) -> str:
+    """
+    Create a new user workflow.
+
+    Args:
+        name: Workflow name (becomes the filename stem, e.g. 'my-custom')
+        content: Full YAML content of the workflow
+
+    Returns:
+        Success message with file path, or error message.
+    """
+    result = create_workflow_impl({"name": name, "content": content})
+    if isinstance(result, list) and result:
+        return result[0].text if hasattr(result[0], "text") else str(result[0])
+    return str(result)
+
+
+@safe_tool_decorator(
+    description="Update (overwrite) an existing user workflow. Cannot update bundled workflows."
+)
+async def update_workflow(name: str, content: str) -> str:
+    """
+    Update an existing user workflow.
+
+    Args:
+        name: Workflow name to update
+        content: New YAML content
+
+    Returns:
+        Success message, or error if workflow is bundled or invalid.
+    """
+    result = update_workflow_impl({"name": name, "content": content})
+    if isinstance(result, list) and result:
+        return result[0].text if hasattr(result[0], "text") else str(result[0])
+    return str(result)
+
+
+@safe_tool_decorator(
+    description="Delete a user workflow by name. Bundled workflows cannot be deleted."
+)
+async def delete_workflow(name: str) -> str:
+    """
+    Delete a user workflow.
+
+    Args:
+        name: Workflow name to delete
+
+    Returns:
+        Success message, or error if workflow is bundled or not found.
+    """
+    result = delete_workflow_impl({"name": name})
+    if isinstance(result, list) and result:
+        return result[0].text if hasattr(result[0], "text") else str(result[0])
+    return str(result)
+
+
 # ============================================================================
 # MAIN ENTRY POINT
 # ============================================================================