ci: separate runtime changes from CI modernization in PR #341

[ss-o]

Context

PR #341 (ci: modernize GitHub Actions — remove bots, SHA-pin actions, add zd integration) includes substantial runtime behaviour changes alongside the CI workflow updates:

• New .zi-auto-reload logic in lib/zsh/autoload.zsh
• Changed .zi-self-update flow (git merge path)
• zpmod build improvements

These runtime changes were not described in the original PR and make code review harder to scope.

Action

When the next focused runtime change is ready, open a dedicated fix(autoload) or feat(zpmod) PR that:

• Covers only runtime changes
• Has its own test evidence (ZUnit run or manual test log)
• References this issue

This issue tracks the split so reviewers can separate CI concerns from behaviour concerns.