feat(tools): add safety annotations for tool compliance

[codyde]

Per feedback from Anthropic on MCP Safety Guidelines and policy to be in their registry, adding the tool safety annotations as follows -

• Add readOnlyHint: true to tools that only read data without modification (such as authentication checks, listing operations, searching, and documentation retrieval)
• Add destructiveHint: false to tools that perform only additive updates (such as creating teams, projects, and DSNs)
• Explicitly set destructiveHint: true for tools that modify or update existing data (such as update operations)
• Consider adding idempotentHint: true for operations that can be safely repeated with the same arguments

Ensure all 19 tools have appropriate safety annotations

• Introduced safety annotations to all tools for MCP directory compliance, including readOnlyHint, destructiveHint, idempotentHint, and openWorldHint.
• Updated relevant tools to include these annotations, ensuring clear communication of tool behavior and data modification capabilities.
• Added documentation on required annotations and their usage patterns to docs/adding-tools.mdc.