chore: move app proxying code to workspaceapps pkg (#6998)

* chore: move app proxying code to workspaceapps pkg

Moves path-app, subdomain-app and reconnecting PTY proxying to the new
workspaceapps.WorkspaceAppServer struct. This is in preparation for
external workspace proxies.

Updates app logout flow to avoid redirecting to coder-logout.${app_host}
on logout. Instead, all subdomain app tokens owned by the logging-out
user will be deleted every time you logout for simplicity sake.

Tests will remain in their original package, pending being moved to an
apptest package (or similar).

Co-authored-by: Steven Masley <stevenmasley@coder.com>

coderd/database/queries/apikeys.sql

@@ -66,12 +66,18 @@ WHERE
 	id = $1;
 
 -- name: DeleteAPIKeyByID :exec
-DELETE
-FROM
+DELETE FROM
 	api_keys
 WHERE
 	id = $1;
 
+-- name: DeleteApplicationConnectAPIKeysByUserID :exec
+DELETE FROM
+	api_keys
+WHERE
+	user_id = $1 AND
+	scope = 'application_connect'::api_key_scope;
+
 -- name: DeleteAPIKeysByUserID :exec
 DELETE FROM
 	api_keys