Hello,
In /etc/network/interfaces you set your IP to
address 2a06:1700:0:1b::
which is equivalent of 2a06:1700:0:1b:0:0:0:0, or also 2a06:1700:0:1b::0.
But then in torrc you use:
ORPort [2a06:1700:0:1b::1]:9001
From your configs, this is your upstream gateway IP, not IP of your actual
machine. So this configuration is incorrect.
Also generally it is adviced against using the all-zeroes IP (which you
chose), it has some special properties and some software may not support it
properly.
Assuming the entire /64 is assigned to you by the host and the gateway
is ..::1 in it, it's a fine idea to use ..::2, or just whatever IP other than
the ..::0.
Finally though, neither your gateway nor your machine at its present IP seem to
be reachable from the Internet at the moment. Verify that IPv6 works properly
with ping/trace/curl/wget before trying to use it with more complex apps such
as Tor.