Use full UUIDs in PR Story/Task fields

Always use the full UUID (e.g. E6CC19FC-5469-45BD-AA87-9CDBB23A4A7F) in PR description Story/Task fields. Never abbreviate to just the first segment.

Why: The first 8 chars look like a UUID but are only a prefix. Using them creates misleading references that do not resolve.

How to apply: Before writing Story/Task lines in a PR body, grep for :ID: in the relevant .org files to get the exact full UUID. Do not type UUIDs from memory.