form: rework email confirmation

realized half the info from the signup form wasnt being stored in the JWT
used to create the account after email confirmation, and instead of
adding them, the -whole request- from the browser is stored temporarily
by the server, indexed by a smaller JWT that only includes the invite
code. Someone complained on reddit about me storing the password in the
JWT a while back, and although security-wise that isn't an issue (only
the server can decrypt the token), it doesn't happen anymore. Happy?

main.go

@@ -17,6 +17,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
+	"sync"
 	"syscall"
 	"time"
 
@@ -90,27 +91,29 @@ type appContext struct {
 	adminUsers     []User
 	invalidTokens  []string
 	// Keeping jf name because I can't think of a better one
-	jf               *mediabrowser.MediaBrowser
-	authJf           *mediabrowser.MediaBrowser
-	ombi             *ombi.Ombi
-	datePattern      string
-	timePattern      string
-	storage          Storage
-	validator        Validator
-	email            *Emailer
-	telegram         *TelegramDaemon
-	discord          *DiscordDaemon
-	matrix           *MatrixDaemon
-	info, debug, err *logger.Logger
-	host             string
-	port             int
-	version          string
-	URLBase          string
-	updater          *Updater
-	newUpdate        bool // Whether whatever's in update is new.
-	tag              Tag
-	update           Update
-	internalPWRs     map[string]InternalPWR
+	jf                   *mediabrowser.MediaBrowser
+	authJf               *mediabrowser.MediaBrowser
+	ombi                 *ombi.Ombi
+	datePattern          string
+	timePattern          string
+	storage              Storage
+	validator            Validator
+	email                *Emailer
+	telegram             *TelegramDaemon
+	discord              *DiscordDaemon
+	matrix               *MatrixDaemon
+	info, debug, err     *logger.Logger
+	host                 string
+	port                 int
+	version              string
+	URLBase              string
+	updater              *Updater
+	newUpdate            bool // Whether whatever's in update is new.
+	tag                  Tag
+	update               Update
+	internalPWRs         map[string]InternalPWR
+	ConfirmationKeys     map[string]map[string]newUserDTO // Map of invite code to jwt to request
+	confirmationKeysLock sync.Mutex
 }
 
 func generateSecret(length int) (string, error) {