[tmm]

The Rune zbugs app's (apps/zbugs-rune) pickers now work like the web app's:

• People: the issue's assignee picker and the sidebar's Creator and Assignee filters are Rune Comboboxes that search by login (fuzzy, with arrow keys and Enter), as the web app's UserPicker does. Their triggers look the same as before.
• Labels: the label picker is a popover with a "Filter or add label…" field. It lists the issue's labels first, then the rest, as checkboxes that stay open as you toggle them. When nothing matches, it offers Create "…". Enter does the same unless a label already has that name (in any case). It replaces the "New Label…" sheet, as the web picker has none.
• Escape closes an open picker. Rune's popovers close only on a press outside, so the app's key handler and the pickers' filter fields close them.

e2e.sh now checks a label by name and creates one by typing it and pressing Enter. It passes all eight checks against the backend on macOS. On the Mac I also checked:

• typing "ar" narrows the Creator filter to arv, ingar, cesara, darkgnotic and jamischarles;
• searching "tantaman" in the assignee picker and pressing Enter assigns the issue in Postgres;
• typing "perf" offers Create "perf", and pressing Enter on a new name creates the label and adds it to the issue.