Add tool descriptions to --help output

[0xtus]

Description

When running npx @azeth/mcp-server --help, show a formatted list of all 32 tools with short descriptions.

Why

Developers evaluating the MCP server want to quickly see what tools are available before configuring it. A good --help output acts as instant documentation.

Suggested approach

1. Parse the tool definitions from src/tools/
2. Format as a table or list: tool_name — description
3. Add --list-tools flag as an alternative