Add tiger service logs command and service_logs MCP tool

[nathanjcochran]

Adds a new tiger service logs command for viewing service logs with colorized output and automatic pagination. Also adds corresponding service_logs MCP tool.

Changes

• Add tiger service logs command with --tail, --until, --node, and --output flags
• Default --tail to 100 lines with automatic multi-page fetching as needed
• Add colorized output for PostgreSQL log levels (ERROR/FATAL in red, WARNING in yellow, etc.)

Key Decisions

• Log reversal: API returns logs in descending order (newest first), but terminal convention is oldest first/newest last, so we reverse before displaying
• User-friendly parameters: --node instead of --service-ordinal, --until instead of --start-time (following Docker's convention - see docker logs --help)
• Tail filter logic: Take first N logs from descending list (most recent), then reverse for display
• Default tail: 100 lines is a reasonable default that works for most use cases without overwhelming the terminal or causing a huge number of page fetches (which slows down the command). Users can request more by specifying a larger value for --tail or by specifying an earlier timestamp for --until.

MCP Integration

The service_logs MCP tool was added after the CLI command, sharing the same common.FetchServiceLogs() implementation for consistency.