feat: Improve resource preview and first-time experience (#946)

* Improve CLI documentation

* feat: Allow workspace resources to attach multiple agents

This enables a "kubernetes_pod" to attach multiple agents that
could be for multiple services. Each agent is required to have
a unique name, so SSH syntax is:

`coder ssh <workspace>.<agent>`

A resource can have zero agents too, they aren't required.

* Add tree view

* Improve table UI

* feat: Allow workspace resources to attach multiple agents

This enables a "kubernetes_pod" to attach multiple agents that
could be for multiple services. Each agent is required to have
a unique name, so SSH syntax is:

`coder ssh <workspace>.<agent>`

A resource can have zero agents too, they aren't required.

* Rename `tunnel` to `skip-tunnel`

This command was `true` by default, which causes
a confusing user experience.

* Add disclaimer about editing templates

* Add help to template create

* Improve workspace create flow

* Add end-to-end test for config-ssh

* Improve testing of config-ssh

* Fix workspace list

* Fix config ssh tests

* Update cli/configssh.go

Co-authored-by: Cian Johnston <public@cianjohnston.ie>

* Fix requested changes

* Remove socat requirement

* Fix resources not reading in TTY

Co-authored-by: Cian Johnston <public@cianjohnston.ie>

cli/cliui/select.go

@@ -1,11 +1,13 @@
 package cliui
 
 import (
+	"errors"
 	"flag"
 	"io"
 	"os"
 
 	"github.com/AlecAivazis/survey/v2"
+	"github.com/AlecAivazis/survey/v2/terminal"
 	"github.com/spf13/cobra"
 )
 
@@ -48,7 +50,6 @@ func Select(cmd *cobra.Command, opts SelectOptions) (string, error) {
 	if flag.Lookup("test.v") != nil {
 		return opts.Options[0], nil
 	}
-	opts.HideSearch = false
 	var value string
 	err := survey.AskOne(&survey.Select{
 		Options:  opts.Options,
@@ -63,6 +64,9 @@ func Select(cmd *cobra.Command, opts SelectOptions) (string, error) {
 	}, fileReadWriter{
 		Writer: cmd.OutOrStdout(),
 	}, cmd.OutOrStdout()))
+	if errors.Is(err, terminal.InterruptErr) {
+		return value, Canceled
+	}
 	return value, err
 }