Add detailed architecture diagram to README for Wikimedia Dumps pipeline

[alizahh-7]

The current README provides a textual explanation of the Wikimedia Dumps automation workflow, but it lacks a visual representation of how the different components interact with each other.

To improve onboarding for new contributors and make the system easier to understand, a detailed architecture diagram should be added to the README.

Proposed update:

1. Add a Mermaid-based flowchart that illustrates the complete high-level pipeline, including:
2. Wikimedia dumps HTML pages (dumps.wikimedia.org)
3. Crawling and HTML parsing using wiki_dumps_crawler.py
4. Detection of newly published and finished dumps
5. Storage of discovered dump URLs in crawled_urls.txt
6. Publishing workflow via wikimedia_publish.py
7. Publication of RDF metadata to the Databus API
8. Availability of metadata in the Databus knowledge graph for SPARQL queries

The diagram should clearly show:

1. Data flow between components
2. Decision points (e.g., presence of new dumps)
3. The end-to-end automation from dump discovery to Databus publication

This visual overview will make the repository more accessible to first-time contributors and clarify how the crawler and publishing scripts work together within the DBpedia infrastructure.

[alizahh-7]

Hii Dbpedians kinldy chk this out!!
#6