List the user modes in the 004 reply (closes #220)

Both transports sent an empty string as the user modes in RPL_MYINFO.
On the IRC listener that left an empty parameter in the middle of the
line, so a client that splits on spaces read the channel modes as the
user modes. The reply now lists o and w, the user modes the server
supports. Both transports read them from one constant in
internal/service, next to the code that decides which user modes MODE
accepts. The README and the schema notes now show what the HTTP API
sends.

Model: opus-5-5

internal/handlers/api.go

@@ -412,7 +412,7 @@ func (hdlr *Handlers) deliverWelcome(
 	// 004 RPL_MYINFO
 	hdlr.enqueueNumeric(
 		ctx, clientID, irc.RplMyInfo, nick,
-		[]string{srvName, version, irc.UserModes, "ikmnostl"},
+		[]string{srvName, version, service.UserModes, "ikmnostl"},
 		"",
 	)
 

internal/ircserver/conn.go

@@ -605,7 +605,7 @@ func (c *Conn) deliverWelcome() {
 	)
 	c.sendNumeric(
 		irc.RplMyInfo,
-		c.serverSfx, "neoirc", irc.UserModes, "mnst",
+		c.serverSfx, "neoirc", service.UserModes, "mnst",
 	)
 	c.sendNumeric(
 		irc.RplIsupport,

internal/service/service.go

@@ -1169,6 +1169,12 @@ func (s *Service) ApplyUserMode(
 	return s.QueryUserMode(ctx, sessionID)
 }
 
+// UserModes lists the user modes the server supports, as
+// RPL_MYINFO sends them: o (server operator) and w
+// (receives WALLOPS). parseUserModeString must accept the
+// same letters.
+const UserModes = "ow"
+
 // parseUserModeString parses a user mode string such as
 // "+w", "-o" or "+w-o" into the new value of each flag it
 // names, or nil for a flag it does not name; a later letter

pkg/irc/numerics.go

@@ -65,11 +65,6 @@ const (
 	RplIsupport IRCMessageType = 5 // De-facto standard (same numeric as RplBounce)
 )
 
-// UserModes lists the user modes the server supports, as
-// RPL_MYINFO sends them: o (server operator) and w
-// (receives WALLOPS).
-const UserModes = "ow"
-
 // Command responses (200-399).
 const (
 	// RFC 2812 trace/stats/links replies (200-219).