Add Indonesian translation

[Yoruxyv]

Summary

• add Indonesian (id) localization to Language.xml
• add id-ID culture detection and Bahasa Indonesia to the language selector
• add README_ID.md
• add Bahasa Indonesia links to the existing README navigation

Validation

• verified XML parsing successfully
• confirmed English/Indonesian parity at 248/248 keys
• confirmed no missing, extra, duplicate, or empty localization entries
• verified key ordering matches the English source
• preserved whitespace-sensitive values
• preserved file filter pipe/wildcard structure
• preserved Windows/API identifiers, file extensions, shortcuts, and priority values
• verified the final diff with git diff --check
• manually reviewed the Indonesian wording for consistency and natural phrasing

Testing

Static validation was completed successfully. Runtime build verification was not performed in this environment because the project targets the legacy Visual Studio 2019 / .NET Framework 4 toolchain.