feat(ext/popup): field-row + concealed-row + signature-block helpers

extension/src/popup/styles.css

@@ -459,3 +459,52 @@ textarea {
   border-color: #3fb950;
   border-style: solid;
 }
+
+/* --- field-row + signature-block helpers (β₁) --- */
+
+.field-row {
+  display: grid;
+  grid-template-columns: 90px 1fr auto;
+  gap: 8px 10px;
+  align-items: baseline;
+  padding: 4px 0;
+  font-size: 12px;
+}
+
+.field-row__label   { color: #8b949e; }
+.field-row__value   { color: #c9d1d9; word-break: break-word; }
+.field-row__value.monospace { font-family: "SF Mono", "JetBrains Mono", monospace; }
+.field-row__value pre {
+  margin: 0;
+  white-space: pre-wrap;
+  word-break: break-word;
+  font-family: "SF Mono", "JetBrains Mono", monospace;
+}
+.field-row__actions {
+  display: flex;
+  gap: 6px;
+  font-size: 11px;
+  color: #8b949e;
+}
+.field-row__actions button {
+  background: transparent;
+  border: 0;
+  color: inherit;
+  cursor: pointer;
+  padding: 0;
+  font: inherit;
+}
+.field-row__actions button:hover { color: #c9d1d9; }
+
+.sig-block {
+  background: #161b22;
+  border: 1px solid #30363d;
+  border-left: 3px solid #1f6feb;
+  border-radius: 5px;
+  padding: 14px;
+  margin-bottom: 10px;
+}
+.sig-block--blue  { border-left-color: #1f6feb; }
+.sig-block--green { border-left-color: #3fb950; }
+.sig-block--amber { border-left-color: #d29922; }
+.sig-block--red   { border-left-color: #f85149; }