admin: tables fit a phone, their first cell carrying the hidden columns, and no positioned label widens the page

admin/src/styles.css

@@ -32,8 +32,15 @@
 	 * chevron, and Segoe UI does not carry that glyph, so on Windows the stack
 	 * has to reach a font that does before it falls back to a substitute box.
 	 */
+	/*
+	 * `overflow-wrap: break-word` breaks a word only where it cannot fit its line:
+	 * a group or source name is the user's text and can be one unbroken string
+	 * wider than a phone. It leaves min-content alone, so a table cell or a flex
+	 * item that holds such a name still needs `anywhere` of its own.
+	 */
 	html {
 		line-height: 1.5;
+		overflow-wrap: break-word;
 		-webkit-text-size-adjust: 100%;
 		/* The tokens carry both schemes; this tells the UA to match its own chrome — form controls, scrollbars. */
 		color-scheme: light dark;