feat: v0.5.0 — welle B Teil 1 (registry tools: search, tags, pull)

Three new SYNO.Docker.Registry tools, reverse-engineered from a live
DSM API capture (n4s4 reference disagrees on param names and methods).

- search_registry (#5): SYNO.Docker.Registry/search v1 with JSON-encoded
  q, plus offset/limit/page_size. Renders stars, downloads, official
  flag, truncated description, and total match count. Read-only.
- list_image_tags: SYNO.Docker.Registry/tags v1 with JSON-encoded repo
  (not name — DSM live capture diverges from n4s4). Response shape is
  unusual: tag list comes back as the envelope's data field directly.
  Output capped by limit (default 50); accepts both list and dict
  response shapes defensively. Read-only.
- pull_image (#3): SYNO.Docker.Registry/pull_start v1 with both
  repository and tag JSON-encoded. Async pull — no pull_status method
  confirmed on this DSM, so completion is detected by polling
  SYNO.Docker.Image/list (2–10 s backoff, 240 s budget under the
  Claude Desktop ~4 min tool-call ceiling). Timeout returns a
  non-fatal "still running" hint. Short-circuits when the image is
  already present locally. Confirmation gate required.

Tool count: 31 → 34. CLAUDE.md confirmation list updated. New DSM
quirks documented for pull_start (no pull_status) and tags (repo
param name, top-level data array).

Closes #3
Closes #5

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

CHANGELOG.md

@@ -2,7 +2,40 @@
 
 All notable changes to this project will be documented in this file.
 
-## [0.4.3] - 2026-05-18
+## [0.5.0] - 2026-05-18
+
+### Added
+
+**Welle B Teil 1 — Registry tools (#3, #5).** Three new `SYNO.Docker.Registry`
+tools, reverse-engineered from a live DSM API capture (the n4s4 reference
+disagrees on parameter names and methods; the live capture wins):
+
+- `search_registry` (#5) — search the active Docker registry by query string.
+  Uses `SYNO.Docker.Registry/search` (version 1) with the query JSON-encoded
+  as `q`, plus `offset`, `limit`, and `page_size`. Renders stars, downloads,
+  the official-image flag, and a truncated description per hit, and shows
+  the total match count so the caller knows when to raise `limit`. No
+  confirmation gate (read-only).
+- `list_image_tags` — list available tags for a repository (bonus tool).
+  Uses `SYNO.Docker.Registry/tags` (version 1) with the repository
+  JSON-encoded as `repo` — note the parameter name diverges from the n4s4
+  reference which uses `name`. The response shape is unusual: DSM returns
+  the tag list as the envelope's `data` field directly (not wrapped in a
+  sub-key), so the tool accepts both shapes defensively. Output is capped
+  by `limit` (default 50) because popular images like `alpine` ship 200+
+  tags. No confirmation gate (read-only).
+- `pull_image` (#3) — pull an image into the local cache via
+  `SYNO.Docker.Registry/pull_start` (version 1) with both `repository` and
+  `tag` JSON-encoded. Requires `confirmed=True`. DSM exposes no confirmed
+  `pull_status` method, so completion is detected by polling
+  `SYNO.Docker.Image/list` for the new `repository:tag` pair with a 2–10 s
+  backoff schedule and a 240 s overall budget (kept under the Claude
+  Desktop ~4 min tool-call ceiling). A timeout returns a non-fatal "still
+  running" hint pointing at `list_images` instead of raising — DSM keeps
+  pulling server-side regardless. Short-circuits when the image is already
+  present locally so a repeated call is cheap. Closes #3 and #5.
+
+Tool count rises from 31 to 34.
 
 ### Fixed