Add MAUI Day Cologne for dotnet

[confs-tech-bot]

Conference information

Website: https://mauiday.net/cologne
CFP: https://sessionize.com/mauiday-cologne-2026
Bluesky: mauiday.net

Github: @tonyedwardspz
Twitter: https://twitter.com/@mauiday

// dotnet

{
  "name": "MAUI Day Cologne",
  "url": "https://mauiday.net/cologne",
  "startDate": "2026-10-23",
  "endDate": "2026-10-23",
  "city": "Cologne",
  "country": "Germany",
  "online": false,
  "locales": "EN",
  "cocUrl": "https://mauiday.net/code-of-conduct/",
  "cfpUrl": "https://sessionize.com/mauiday-cologne-2026",
  "cfpEndDate": "2026-08-01",
  "bluesky": "mauiday.net",
  "twitter": "@mauiday"
}