Remove fomantic message module (#29856)

Remove this CSS-only module, which gives a nice reduction in CSS size.
Should look exactly like before.

Author: silverwind

web_src/css/base.css

@@ -510,73 +510,6 @@ ol.ui.list li,
   visibility: visible !important;
 }
 
-.ui.message {
-  background: var(--color-box-body);
-  color: var(--color-text);
-  box-shadow: none !important;
-  border: 1px solid var(--color-secondary);
-}
-
-.ui.info.message .header,
-.ui.blue.message .header {
-  color: var(--color-blue);
-}
-
-.ui.info.message,
-.ui.attached.info.message,
-.ui.blue.message,
-.ui.attached.blue.message {
-  background: var(--color-info-bg);
-  color: var(--color-info-text);
-  border-color: var(--color-info-border);
-}
-
-.ui.success.message .header,
-.ui.positive.message .header,
-.ui.green.message .header {
-  color: var(--color-green);
-}
-
-.ui.success.message,
-.ui.attached.success.message,
-.ui.positive.message,
-.ui.attached.positive.message {
-  background: var(--color-success-bg);
-  color: var(--color-success-text);
-  border-color: var(--color-success-border);
-}
-
-.ui.error.message .header,
-.ui.negative.message .header,
-.ui.red.message .header {
-  color: var(--color-red);
-}
-
-.ui.error.message,
-.ui.attached.error.message,
-.ui.red.message,
-.ui.attached.red.message,
-.ui.negative.message,
-.ui.attached.negative.message {
-  background: var(--color-error-bg);
-  color: var(--color-error-text);
-  border-color: var(--color-error-border);
-}
-
-.ui.warning.message .header,
-.ui.yellow.message .header {
-  color: var(--color-yellow);
-}
-
-.ui.warning.message,
-.ui.attached.warning.message,
-.ui.yellow.message,
-.ui.attached.yellow.message {
-  background: var(--color-warning-bg);
-  color: var(--color-warning-text);
-  border-color: var(--color-warning-border);
-}
-
 .ui.error.header {
   background: var(--color-error-bg) !important;
   color: var(--color-error-text) !important;

web_src/css/index.css

@@ -12,6 +12,7 @@
 @import "./modules/divider.css";
 @import "./modules/svg.css";
 @import "./modules/flexcontainer.css";
+@import "./modules/message.css";
 
 @import "./shared/flex-list.css";
 @import "./shared/milestone.css";

web_src/css/modules/message.css

@@ -0,0 +1,99 @@
+.ui.message {
+  background: var(--color-box-body);
+  color: var(--color-text);
+  border: 1px solid var(--color-secondary);
+  position: relative;
+  min-height: 1em;
+  margin: 1em 0;
+  padding: 1em 1.5em;
+  border-radius: var(--border-radius);
+}
+
+.ui.message:first-child {
+  margin-top: 0;
+}
+
+.ui.message:last-child {
+  margin-bottom: 0;
+}
+
+.ui.attached.message {
+  margin-bottom: -1px;
+  border-radius: var(--border-radius) var(--border-radius) 0 0;
+  margin-left: -1px;
+  margin-right: -1px;
+}
+
+.ui.attached + .ui.attached.message:not(.top):not(.bottom) {
+  margin-top: -1px;
+  border-radius: 0;
+}
+
+.ui.bottom.attached.message {
+  margin-top: -1px;
+  border-radius: 0 0 var(--border-radius) var(--border-radius);
+}
+
+.ui.bottom.attached.message:not(:last-child) {
+  margin-bottom: 1em;
+}
+
+.ui.info.message .header,
+.ui.blue.message .header {
+  color: var(--color-blue);
+}
+
+.ui.info.message,
+.ui.attached.info.message,
+.ui.blue.message,
+.ui.attached.blue.message {
+  background: var(--color-info-bg);
+  color: var(--color-info-text);
+  border-color: var(--color-info-border);
+}
+
+.ui.success.message .header,
+.ui.positive.message .header,
+.ui.green.message .header {
+  color: var(--color-green);
+}
+
+.ui.success.message,
+.ui.attached.success.message,
+.ui.positive.message,
+.ui.attached.positive.message {
+  background: var(--color-success-bg);
+  color: var(--color-success-text);
+  border-color: var(--color-success-border);
+}
+
+.ui.error.message .header,
+.ui.negative.message .header,
+.ui.red.message .header {
+  color: var(--color-red);
+}
+
+.ui.error.message,
+.ui.attached.error.message,
+.ui.red.message,
+.ui.attached.red.message,
+.ui.negative.message,
+.ui.attached.negative.message {
+  background: var(--color-error-bg);
+  color: var(--color-error-text);
+  border-color: var(--color-error-border);
+}
+
+.ui.warning.message .header,
+.ui.yellow.message .header {
+  color: var(--color-yellow);
+}
+
+.ui.warning.message,
+.ui.attached.warning.message,
+.ui.yellow.message,
+.ui.attached.yellow.message {
+  background: var(--color-warning-bg);
+  color: var(--color-warning-text);
+  border-color: var(--color-warning-border);
+}