Merge pull request #3 from calumbest/feature/read-sheet-hyperlinks

Add read_sheet_hyperlinks tool for extracting embedded URLs from cells

Switch setup from download to git clone, add update instructions

Update README to document blocked destructive operations

Cross-platform credential storage via keyring backend validation

Security: Block trashing of Drive files and Gmail messages

Add value_render_option parameter to read_sheet_values

fixed documentation on stateless

Security: Emphasize that hardening reduces but doesn't eliminate exfiltration risk

Security: Document remaining exfiltration risks

Security: Remove calendar event attendees parameter

Security cleanup: rename markers and fix tool_tiers.yaml

Add macOS Keychain credential storage to README, fix GitHub URLs

Initial release: Security-hardened Google Workspace MCP for Claude Code