feat: opencode release v1.18.15

[github-actions]

What's Changed

Core

Bugfixes

• Chronological message ordering now stays correct even when imported or legacy message IDs are out of order.
• Revert and fork actions now use real message chronology instead of message ID ordering.
• Truncation cleanup now removes stale files by file timestamp more reliably.
• Repeated compaction now keeps earlier tool-call history in summaries instead of dropping orphaned results.
• Blob-based attachments now load correctly in the web UI. (@rexdotsh)

Desktop

Improvements

• Added much broader locale coverage across the desktop app.
• Export full session transcripts as JSON from the UI.

Bugfixes

• Session timelines now respect chronological message boundaries more reliably.
• Stored messages now stay ordered by creation time.
• Session lists now sort by persisted activity time more reliably.
• Language names now stay native in the locale picker.
• Filled in missing translations across existing locales.

Thank you to 3 community contributors:

• @rexdotsh:
  • fix(server): allow blob attachments in web UI (#40692)
• @ayubun:
  • fix(tui): support copying over ssh with set-clipboard on tmux config (#30472)
• @dangooddd:
  • feat(tui): add cursor style configuration (#32295)

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Full Changelog: https://github.com/anomalyco/opencode/releases/tag/v1.18.15

This PR was created automatically by a scheduled workflow.