Replace Clay with n8n, Ollama, SearXNG and browserless; add Telegram assistant

Remove the Clay role (Claude Code web UI) and its Anthropic API key.

New roles:
- ollama: local CPU LLM (qwen3:4b-instruct), internal network only
- browserless: headless Chromium for JavaScript-heavy pages
- searxng: metasearch backend for the chat web_search tool
- n8n at agent.ladkau.de: web chat (/chat), scheduled workflows,
  Telegram bot; workflows and credentials are imported from the repo

Telegram bot: Gemini 3.8 -> Gemini 3.5 -> local Qwen fallback chain,
/qwen to force the local model, /stocks and a weekday schedule
(07:30, 13:00, 17:40) for the MTE.DE / PTX.F stock report.

Also: dashboard and check-services entries for the chat, vault checks
for the new secrets (n8n, SearXNG, Gemini, Telegram, SMTP), updated
CLAUDE.md, runbooks and README.

ansible/roles/browserless/tasks/main.yml

@@ -0,0 +1,26 @@
+---
+- name: Create Browserless directory
+  ansible.builtin.file:
+    path: "{{ browserless_data_dir }}"
+    state: directory
+    owner: root
+    group: root
+    mode: "0755"
+  tags: browserless
+
+- name: Deploy Docker Compose file
+  ansible.builtin.template:
+    src: docker-compose.yml.j2
+    dest: "{{ browserless_data_dir }}/docker-compose.yml"
+    owner: root
+    group: root
+    mode: "0644"
+  notify: Restart browserless
+  tags: browserless
+
+- name: Start Browserless
+  community.docker.docker_compose_v2:
+    project_src: "{{ browserless_data_dir }}"
+    state: present
+    pull: missing
+  tags: browserless