fix: fetch tags in agent checkout before computing next release version

[Copilot]

The create_release job was failing with fatal: tag 'v0.0.1' already exists because the agent runs in a shallow checkout (fetch-depth: 1) with no tags. git tag --list returned nothing, the fallback v0.0.0 kicked in, and the AI dutifully computed v0.0.1 — a tag that already existed.

Changes

• create-release.md Step 1: add git fetch --tags before the tag listing command; replace git tag --sort=-version:refname | head -n 1 with sort -V | tail -n 1 (more portable across git versions and container environments)
• create-release.lock.yml: recompiled via gh aw compile create-release --strict

# Before
PREVIOUS_TAG=$(git tag --list 'v[0-9]*.[0-9]*.[0-9]*' --sort=-version:refname | head -n 1)

# After
git fetch --tags
PREVIOUS_TAG=$(git tag -l 'v[0-9]*.[0-9]*.[0-9]*' | sort -V | tail -n 1)