.dump fails if the request is sent to replica

[avinassh]

Recently, a user tried to take an export, but the database panicked. The logs pointed to an unwrap here:

libsql/libsql-server/src/http/user/dump.rs

Lines 93 to 95 in f66dcf7

	.with(namespace, |ns| {
	ns.db.as_primary().unwrap().connection_maker()
	})

As a workround, user was able to take the export by force connecting to primary and calling .dump

first reported in discord: https://discord.com/channels/933071162680958986/933071163184283651/1256427537328767009

[MarinPostma]

I think replicas should proxy the call to the primary