Introduced a new script `check-internal-links.py` to validate internal file links in markdown files. Updated the `quality-assurance.yml` workflow to include the internal link check. Removed references to the deleted `financial-analyzer.md` file across documentation and related prompts.
Added a new .markdownlint.json configuration file to manage markdown linting rules. Removed .spellcheck.yml and .wordlist.txt as they are no longer needed. Updated several markdown files to simplify content and remove outdated references.