Bug, feature, and question templates now collect the triage signal the
maintainers usually have to ask for (install method, OS, area, reverse
proxy, logs, version). config.yml disables blank issues and points to
Wiki / existing issues / latest release from the picker.
PR template adds Summary/Why/Type/Areas/Testing/Breaking-changes
sections and a fuller checklist (build, tests, lint, typecheck, docs).
Renamed pull_request_template.yml -> .md to match GitHub's conventional
extension; the old .yml was being read as markdown anyway.
