Project Tool: File Uploads Now Visible and Readable

The Project tool (project_info, project_read, project_delete) now surfaces file uploads (PDFs, images, and other binary files) alongside text docs.

• project_info output now includes a ## Project files (N) section listing file uploads and a ## Synced sources (N) section listing connector-synced content (Google Drive, GitHub, Outline, MCP resources)
• project_read on a file upload returns a file_kind field; for document-type uploads (PDF, docx) it returns extracted text; for other types it returns empty content with a notice explaining that no text extract is available
• project_delete on a file upload now returns a clear error explaining that file uploads can only be removed from claude.ai, not via the tool
• The error message when a path is not found now says "No doc or file at" instead of "No doc at" and lists both docs and files