Fixes all our Go file imports to match the preferred spec that we've _mostly_ been using. For example:
```
import (
"context"
"time"
"github.com/prometheus/client_golang/prometheus"
"golang.org/x/xerrors"
"gopkg.in/natefinch/lumberjack.v2"
"cdr.dev/slog/v3"
"github.com/coder/coder/v2/codersdk/agentsdk"
"github.com/coder/serpent"
)
```
3 groups: standard library, 3rd partly libs, Coder libs.
This PR makes the change across the codebase. The PR in the stack above modifies our formatting to maintain this state of affairs, and is a separate PR so it's possible to review that one in detail.
Upgrades to slog v3 which includes a small, but backward incompatible API change to the acceptible call arguments when logging. This change allows us to verify via compile time type checking that arguments are correct and won't cause a panic, as was possible in slog v1, which this replaces (v2 was tagged but never used in coder/coder).
It also updates dependencies that also use slog and were updated.
I've left the `aibridge` dependency as a commit SHA, under the assumption that the team there (cc @pawbana @dannykopping ) will tag and update the dependency soon and on their own schedule.
Other dependencies, I pushed new tags.
Refactors tailnet integration test and adds UDP echo tests with different MTU related to #15523
I still haven't gotten to the bottom of what's causing the issue (the added test case I expected to fail actually succeeds), but these integration test improvements are generally useful.
also:
* consolidates networking setup with easy and hard NAT
* consolidates client setup
* makes Client2 act like an agent at the tailnet layer, so it will send ReadyForHandshake and speed up the tunnel establishment
* adds support for logging tunneled packets
* adds support for dumping outer (underlay) IP traffic
* adds support for adjusting veth MTU
* adds support for IPv6 in the outer (underlay) network topology
re: #14715
This PR introduces the Coder service prefix: `fd60:627a:a42b::/48` and refactors our existing code as calling the Tailscale service prefix explicitly (rather than implicitly).
Removes the unused `Addresses` agent option. All clients today assume they can compute the Agent's IP address based on its UUID, so an agent started with a custom address would break things.