`weed server -ip.bind=127.0.0.1` keeps every listener local, but the
same address became the source of outbound connections, so the filer
dialled its remote mount from 127.0.0.1 and failed with "connect:
invalid argument". A loopback source cannot reach off the host; leave
the source to the OS, as for a wildcard bind.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
* ip.bind: bind outbound connections to the configured address
-ip.bind only governed listeners; outbound gRPC and HTTP connections let
the OS pick the source IP, which may not even be able to reach the
target. Mirror the bind address into a process-global source address and
apply it to outbound TCP dials: the gRPC context dialer, the per-client
HTTP transports, and the default transport. Loopback targets and unix
sockets keep the OS-chosen source so same-host traffic still works.
* ip.bind: first-write-wins source IP, skip on address-family mismatch
Make SetOutboundLocalIP first-write-wins so a `weed server` component's own
bind setting (run in its goroutine) can't clobber the process-wide source
address the top-level -ip.bind already established for the other components.
Skip source binding when the target is a literal IP of a different family
than the bind address, since forcing a mismatched source fails the dial.
