Remove pull_image + list_registries; mark Gruppen 6+7 as entfällt

DSM methods for SYNO.Docker.Image/pull and SYNO.Docker.Registry/get
did not behave as expected in production testing against the NAS.
Tools deregistered, modules deleted, tests removed, CLAUDE.md updated.
Tool count: 19 → 17.

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

src/mcp_synology_container/modules/images.py

@@ -1,8 +1,7 @@
-"""MCP tools for SYNO.Docker.Image: list, check updates, delete, pull."""
+"""MCP tools for SYNO.Docker.Image: list, check updates, delete."""
 
 from __future__ import annotations
 
-import asyncio
 import json
 import logging
 import sys
@@ -270,56 +269,6 @@ def register_images(mcp: FastMCP, config: AppConfig, client: DsmClient) -> None:
 
         return f"Deleted {display_name} — {size_str} freed."
 
-    @mcp.tool()
-    async def pull_image(image: str) -> str:
-        """Pull a Docker image from the active registry.
-
-        Splits the image reference into repository and tag, triggers the pull
-        via DSM, then polls the image list until the image appears (up to 120 s).
-
-        Args:
-            image: Image reference as "name:tag" (e.g. "postgres:17.8").
-                   Tag defaults to "latest" when omitted.
-        """
-        repository, sep, tag = image.rpartition(":")
-        if not sep:
-            repository = image
-            tag = "latest"
-
-        try:
-            await client.request(
-                "SYNO.Docker.Image",
-                "pull",
-                params={"repository": repository, "tag": tag},
-            )
-        except Exception as e:
-            return f"Error starting pull of '{image}': {e}"
-
-        # DSM starts the pull asynchronously; poll until the image appears.
-        deadline = 120
-        interval = 3
-        elapsed = 0
-        while elapsed < deadline:
-            await asyncio.sleep(interval)
-            elapsed += interval
-            try:
-                img_data = await client.request(
-                    "SYNO.Docker.Image",
-                    "list",
-                    params={"limit": "-1", "offset": "0", "show_dsm": "false"},
-                )
-            except Exception:
-                continue
-            for img in img_data.get("images", []):
-                if img.get("repository") == repository and tag in (img.get("tags") or []):
-                    size_str = _human_size(img.get("size", 0))
-                    return f"Pulled {repository}:{tag} — {size_str}."
-
-        return (
-            f"Pull of '{repository}:{tag}' started but did not complete within "
-            f"{deadline} s. Check DSM Container Manager for status."
-        )
-
     @mcp.tool()
     async def check_image_updates(project_name: str | None = None) -> str:
         """Check for available image updates for a project or all images.