users: huge cleanup/dedupe, interface-based third-party services

shared "newUser" method is now "NewUserPostVerification", and is shared
between all routes which create a jellyfin account. The new
"NewUserFromInvite", "NewUserFromAdmin" and "NewUserFromConfirmationKey"
are smaller as a result. Discord, Telegram, and Matrix now implement the
"ContactMethodLinker" and "ContactMethodUser" interfaces, meaning code
is shared a lot between them in the NewUser methods, and the specifics
are now in their own files. Ombi/Jellyseerr similarly implement a
simpler interface "ThirdPartyService", which simply has ImportUser and
AddContactMethod routes. Note these new interface methods are only used
for user creation as of yet, but could likely be used in other places.

telegram.go

@@ -16,9 +16,27 @@ const (
 )
 
 type TelegramVerifiedToken struct {
-	ChatID     int64
-	Username   string
-	JellyfinID string // optional, for ensuring a user-requested change is only accessed by them.
+	JellyfinID string `badgerhold:"key"` // optional, for ensuring a user-requested change is only accessed by them.
+	ChatID     int64  `badgerhold:"index"`
+	Username   string `badgerhold:"index"`
+}
+
+func (tv TelegramVerifiedToken) ToUser() *TelegramUser {
+	return &TelegramUser{
+		TelegramVerifiedToken: tv,
+	}
+}
+
+func (t *TelegramVerifiedToken) Name() string                 { return t.Username }
+func (t *TelegramVerifiedToken) SetMethodID(id any)           { t.ChatID = id.(int64) }
+func (t *TelegramVerifiedToken) MethodID() any                { return t.ChatID }
+func (t *TelegramVerifiedToken) SetJellyfin(id string)        { t.JellyfinID = id }
+func (t *TelegramVerifiedToken) Jellyfin() string             { return t.JellyfinID }
+func (t *TelegramUser) SetAllowContactFromDTO(req newUserDTO) { t.Contact = req.TelegramContact }
+func (t *TelegramUser) SetAllowContact(contact bool)          { t.Contact = contact }
+func (t *TelegramUser) AllowContact() bool                    { return t.Contact }
+func (t *TelegramUser) Store(st *Storage) {
+	st.SetTelegramKey(t.Jellyfin(), *t)
 }
 
 // VerifToken stores details about a pending user verification token.
@@ -274,7 +292,39 @@ func (t *TelegramDaemon) UserExists(username string) bool {
 	return err != nil || c > 0
 }
 
-// DeleteVerifiedToken removes the token with the given PIN.
-func (t *TelegramDaemon) DeleteVerifiedToken(pin string) {
-	delete(t.verifiedTokens, pin)
+// Exists returns whether or not the given user exists.
+func (t *TelegramDaemon) Exists(user ContactMethodUser) bool {
+	return t.UserExists(user.Name())
 }
+
+// DeleteVerifiedToken removes the token with the given PIN.
+func (t *TelegramDaemon) DeleteVerifiedToken(PIN string) {
+	delete(t.verifiedTokens, PIN)
+}
+
+func (t *TelegramDaemon) PIN(req newUserDTO) string { return req.TelegramPIN }
+
+func (t *TelegramDaemon) Name() string { return lm.Telegram }
+
+func (t *TelegramDaemon) Required() bool {
+	return t.app.config.Section("telegram").Key("required").MustBool(false)
+}
+
+func (t *TelegramDaemon) UniqueRequired() bool {
+	return t.app.config.Section("telegram").Key("require_unique").MustBool(false)
+}
+
+func (t *TelegramDaemon) UserVerified(PIN string) (ContactMethodUser, bool) {
+	token, ok := t.TokenVerified(PIN)
+	if !ok {
+		return &TelegramUser{}, false
+	}
+	tu := token.ToUser()
+	if lang, ok := t.languages[tu.ChatID]; ok {
+		tu.Lang = lang
+	}
+
+	return tu, ok
+}
+
+func (t *TelegramDaemon) PostVerificationTasks(string, ContactMethodUser) error { return nil }