Maven/npm IDs → computer.kolektiv.* (tzdb)

[LizAinslie]

Parent: #810

Current

• API Maven group: `dev.synapsetech.tzdb`

Target

• `computer.kolektiv.timezonedb` (or `computer.kolektiv.tzdb` if Mey prefers short — confirm in Confirm product name / Kolektiv branding for TimezoneDB #811)

Scope

• Gradle `group`, published coordinates, any Android/JS package names that still say synapsetech
• Docs / README install pins after rename