v0.5.4

The Datastar build by an exported name, and proxies that aren't on loopback.

• template: Datastar() returns the vendored Datastar build and DatastarVersion names it (1.0.4+starbase.c6a6589), so an app serves it with edge.Static.Add instead of reading a path inside template.FS.
• edge: BehindProxies(proxies, h) believes the proxy headers from peers in a list of prefixes too, for a proxy on another host or a container bridge, and walks X-Forwarded-For past every address in them; ParseProxies reads the list and TrustedProxies names it. The template's -trusted-proxies (APP_TRUSTED_PROXIES) is empty by default. Every address in the list can name any client: list only your own proxies.