Attempt to read a markdown file from the analysis directory. First checks analysis/daily/{date}/{filename}, then scans immediate subdirectories (e.g., deep-inspection/, propositions/) for the file. Returns null if the file does not exist, cannot be read, or date is not a valid YYYY-MM-DD string (guards against path traversal).
Attempt to read a markdown file from the analysis directory. First checks
analysis/daily/{date}/{filename}, then scans immediate subdirectories (e.g.,deep-inspection/,propositions/) for the file. Returnsnullif the file does not exist, cannot be read, ordateis not a valid YYYY-MM-DD string (guards against path traversal).