Start Twitch alerts and tickets off on new servers

Every module that can be switched on or off now starts off. A server
with no settings yet reads as off; setting the Twitch alert channel or
running /tickets setup for the first time turns that module on, and
existing settings are left as they are. schema.sql mirrors the API's
migration 000019.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

internal/db/repos/ticketrepo/repo.go

@@ -93,9 +93,10 @@ func (r *Repo) GetSettings(ctx context.Context, guildID int64) (*Settings, error
 	err := r.db.QueryRowContext(ctx, q, guildID).Scan(&s.Enabled, &ch, &logCh, &panel, &s.PanelTitle, &s.PanelDescription, &s.MaxOpenPerUser)
 	switch {
 	case errors.Is(err, sql.ErrNoRows):
+		// Modules start off until the server sets them up.
 		return &Settings{
 			GuildID:          guildID,
-			Enabled:          true,
+			Enabled:          false,
 			PanelTitle:       DefaultPanelTitle,
 			PanelDescription: DefaultPanelDescription,
 			MaxOpenPerUser:   DefaultMaxOpenPerUser,
@@ -109,11 +110,12 @@ func (r *Repo) GetSettings(ctx context.Context, guildID int64) (*Settings, error
 }
 
 // SetChannels saves where tickets live and where transcripts go. A zero log
-// channel clears it.
+// channel clears it. Setting tickets up for the first time turns them on
+// (they start off); after that, the on/off switch is left alone.
 func (r *Repo) SetChannels(ctx context.Context, guildID, channelID, logChannelID int64) error {
 	const q = `
-		INSERT INTO ticket_settings (guild_id, channel_id, log_channel_id)
-		VALUES ($1, $2, $3)
+		INSERT INTO ticket_settings (guild_id, channel_id, log_channel_id, enabled)
+		VALUES ($1, $2, $3, TRUE)
 		ON CONFLICT (guild_id) DO UPDATE SET
 			channel_id = EXCLUDED.channel_id,
 			log_channel_id = EXCLUDED.log_channel_id`