Fix yearly time report pagination

[techgocodingnow]

Summary

• paginate user.contractTimeReport until hasNextPage is false
• guard against missing or repeated cursors and add a multi-page regression test
• bump UpworkBuddy to 1.0.12 (build 13) and update the changelog

Root cause

The Year dashboard requests a full calendar year, but the time-report client
consumed only the first GraphQL connection page. For accounts with enough daily
contract rows, later months were replaced by zero-value chart buckets and the
yearly total was incomplete.

User impact

Year now includes all available monthly hours and project breakdown data instead
of stopping after the first API page.

Validation

• swift test — 160 tests passed
• swift build -c release
• plutil -lint Sources/UpworkBuddy/Info.plist
• verified VERSION and CFBundleShortVersionString are 1.0.12 and
  CFBundleVersion is 13