feat(modules): match commands case-insensitively

Mobile keyboards autocapitalize, so a typed /Ping silently did nothing and
read as the bot being broken. Registered names are lowercase-only per
validateCommand, so folding case cannot make two commands collide, and the
canonical Command.Name still drives stats, metrics, hooks, and logs.

internal/modules/dispatcher.go

@@ -121,6 +121,12 @@ func logCommand(name string, update *models.Update, err error) {
 //
 // Telegram routes /cmd@otherbot only to otherbot, so an @suffix present in
 // the entity addresses *this* bot — no need to verify against our username.
+//
+// Matching is case-insensitive so /PING and /Ping reach the same handler as
+// /ping — mobile keyboards autocapitalize, and a typed command that silently
+// does nothing reads as the bot being broken. Registered names are lowercase by
+// validateCommand, so folding case can never make two commands collide, and the
+// canonical Command.Name still drives stats, metrics, hooks, and logs.
 func matchCommand(name string, update *models.Update) bool {
 	if update == nil || update.Message == nil {
 		return false
@@ -141,7 +147,7 @@ func matchCommand(name string, update *models.Update) bool {
 		if i := strings.IndexByte(tok, '@'); i >= 0 {
 			tok = tok[:i]
 		}
-		if tok == name {
+		if strings.EqualFold(tok, name) {
 			return true
 		}
 	}

internal/modules/dispatcher_test.go

@@ -116,6 +116,30 @@ func TestMatchCommand(t *testing.T) {
 			update: mkUpdate("hi /help", cmd(3, 5)),
 			expect: true,
 		},
+		{
+			name:   "uppercase command matches",
+			want:   "help",
+			update: mkUpdate("/HELP", cmd(0, 5)),
+			expect: true,
+		},
+		{
+			name:   "mixed-case command matches",
+			want:   "help",
+			update: mkUpdate("/Help", cmd(0, 5)),
+			expect: true,
+		},
+		{
+			name:   "uppercase command with botname matches",
+			want:   "help",
+			update: mkUpdate("/HELP@miti99bot", cmd(0, 15)),
+			expect: true,
+		},
+		{
+			name:   "case folding does not match a different command",
+			want:   "help",
+			update: mkUpdate("/INFO", cmd(0, 5)),
+			expect: false,
+		},
 		{
 			name:   "nil update",
 			want:   "help",