Improve copilot-instructions: add Functions v4 model, fix lib path, document build commands

Update docs: reminder date resolution includes day of week in Central Time

Fix reminder date: include day-of-week in Central Time for accurate relative date resolution

Update docs: Graph API credentials for file capture, troubleshooting

Fix file capture: download SharePoint files via Graph API client credentials

Fix file capture: accept base64 from Power Automate, resolve MIME from extension

Fix: accept image-only messages with no text

Fix HTTP body: coalesce null attachments to empty array

Fix function app name to open-brain-func, add storage/vision env vars to docs

Update capture flow docs: attachments in HTTP body, complete Parse JSON schema

Add file capture: images, PDFs, and docs stored in Blob Storage with AI analysis

Update prompts README with reminder feature references

Add calendar reminder feature with digest integration

Update docs and code for new capture flow and bug fixes

Add complete_task and reopen_task tools to MCP server