[Bug] MCP stdio mode: CLI logs lack colors and are suppressed when log level is set via config

[anushakolan]

What happened?

Summary

Two bugs in the CLI logger when running DAB in MCP stdio mode:

1. Missing colors — When --LogLevel <level> is passed, CLI startup logs appear on stderr without color formatting, while engine logs are properly colored.
2. Logs suppressed — When the runtime config file specifies runtime.telemetry.log-level and no --LogLevel CLI flag is provided, CLI startup logs are completely suppressed.

Repro

Bug 1 — Missing colors

dab start --mcp-stdio --LogLevel Information --config <path>\dab-config.json

• Expected: info: label in green.
• Actual: info: label in plain white.

Bug 2 — CLI logs suppressed

dab start --mcp-stdio --config <path>\dab-config.json

…where the config contains:

"runtime": {
  "telemetry": {
    "log-level": { "default": "Information" }
  }
}

• Expected: CLI startup logs appear (version, config file, "Setting minimum LogLevel…").
• Actual: CLI logs are missing entirely.

Impact

• Users relying on config-based log level lose visibility of CLI startup info in MCP mode.
• Inconsistent visual experience for CLI vs engine logs.

Related

• PR Implemented MCP Set Log Level #3419 — MCP Set Log Level
• PR Add MCP notifications/message for log streaming to clients #3484 — MCP notifications/message

Version

2.0

What database are you using?

Azure SQL

What hosting model are you using?

No response

Which API approach are you accessing DAB through?

No response

Relevant log output

Code of Conduct

• I agree to follow this project's Code of Conduct

[anushakolan]

Fix

Branch: dev/anushakolan/fix-mcp-cli-logging

• Cli/Utils.cs — Add IsLogLevelOverriddenByConfig and ConfigLogLevel.
• Cli/ConfigGenerator.cs — Set them when RuntimeConfig.HasExplicitLogLevel() is true.
• Cli/CustomLoggerProvider.cs — Honor both override sources and apply colors before writing to stderr.