Add Kosovo

[fernglin]

This addition is generated by GPT but was manually cross-checked with wikipedia and other sources like the Kosovo Agency of Statistics (https://ask.rks-gov.net/)

[Copilot]

Pull request overview

This PR adds Kosovo (country code XK) to the geographic database with comprehensive country and subdivision data. The addition includes both YAML and JSON formats for country-level information and all 38 municipalities of Kosovo with multilingual names, geographic coordinates, and bounding boxes.

Key changes:

• Country data includes official names in Albanian and Serbian, translations in 9 languages, EUR currency, and border countries
• 38 municipalities with codes, alternative names (Albanian, Serbian, and other variants), and detailed coordinate information
• Data cross-referenced with Kosovo Agency of Statistics and Wikipedia

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 6 comments.

File	Description
data/yaml/countries/xk.yaml	Country metadata for Kosovo including names, languages, borders, codes, and geographic coordinates
data/json/countries/xk.json	JSON representation of Kosovo country data
data/yaml/subdivisions/xk.yaml	Complete list of 38 Kosovo municipalities with multilingual names and coordinates
data/json/subdivisions/xk.json	JSON representation of Kosovo subdivision data

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[oalders]

Closes #30