web: tool cards show what ran — summary line (bash command / file path) + edit/write line diffs (LCS, +/- coloring); 286 tests green

web/src/index.css

@@ -687,6 +687,18 @@ a:hover {
 	font-family: var(--mono);
 	font-size: 12px;
 	color: var(--text);
+	flex-shrink: 0;
+}
+.bubble .tool-card summary .tool-summary {
+	flex: 1;
+	min-width: 40px;
+	overflow: hidden;
+	text-overflow: ellipsis;
+	font-family: var(--mono);
+	color: var(--text-dim);
+}
+.bubble .tool-card summary .tool-status {
+	flex-shrink: 0;
 }
 .bubble .tool-card .tool-body {
 	border-top: 1px solid var(--border);
@@ -1468,3 +1480,36 @@ mark.hit {
 	font-size: 12.5px;
 	color: var(--text);
 }
+
+/* ---------- edit/write diff ---------- */
+
+.tool-diffs {
+	margin-bottom: 10px;
+}
+.diff {
+	margin: 0 0 6px;
+	font-family: var(--mono);
+	font-size: 12px;
+	line-height: 1.5;
+	background: var(--bg-veil);
+	border: 1px solid var(--border);
+	border-radius: 6px;
+	padding: 6px 0;
+	overflow-x: auto;
+	white-space: pre;
+}
+.diff-line {
+	display: block;
+	padding: 0 10px;
+}
+.diff-del {
+	color: var(--danger);
+	background: var(--danger-soft);
+}
+.diff-add {
+	color: var(--ok);
+	background: rgba(52, 211, 153, 0.08);
+}
+.diff-ctx {
+	color: var(--text-faint);
+}