Add typography roles, text primitives, fontkit measurer and layout lint

Txt always sets an absolute line height; RenderTxt never does. Row pins
every cell and stacks when the fill column would be too narrow. IdText and
FitText shrink then chunk or truncate. The fontkit measurer matches react-pdf
text widths exactly. A TypeScript-AST lint test enforces the layout rules
(no lineHeight outside Txt, no non-literal fixed/wrap/minPresenceAhead,
flexGrow needs flexBasis, no stray absolute positioning).

src/pdf/blocks/IdText.tsx

@@ -0,0 +1,64 @@
+import { View } from "@react-pdf/renderer";
+import { getMeasurer, measureToken } from "../engine/measure";
+import { resolveFace, roleToken, type RoleName, type TypeToken } from "../fonts/roles";
+import { chunkIdentifier } from "../model/text";
+import { useAvailableWidth } from "./AvailableWidth";
+import { fitSize, type FitInfo } from "./FitText";
+import { Txt, type TxtProps } from "./Txt";
+
+export interface IdTextInfo extends FitInfo {
+  mode: "single" | "chunked";
+  chunks: string[];
+}
+
+export interface IdTextProps extends Omit<TxtProps, "children" | "role" | "maxLines" | "width" | "grow"> {
+  role: RoleName | TypeToken;
+  children: string;
+  /** Width to fit; defaults to the available width of the enclosing cell. */
+  width?: number;
+  minSize?: number;
+  /** For tests and audits only. */
+  onFit?: (info: IdTextInfo) => void;
+}
+
+/**
+ * Text for identifiers (e-mail, URL, GSTIN, phone). textkit never breaks inside a word, so a long
+ * value would overflow silently. This shrinks it to the role's minimum size; if it is still too wide
+ * it is split at "@ . / - _" into a flex-wrap row of adjacent Text chunks (no gaps, so extraction
+ * joins them back into the original string).
+ */
+export function IdText({ role, children, width, minSize, onFit, ...rest }: IdTextProps) {
+  const avail = useAvailableWidth();
+  const target = width ?? avail;
+  const token = roleToken(role);
+  const fit = fitSize(token, children, target, minSize, { weight: rest.weight, italic: rest.italic });
+
+  if (fit.fits) {
+    onFit?.({ ...fit, mode: "single", chunks: [children] });
+    return <Txt {...rest} role={{ ...token, size: fit.size }}>{children}</Txt>;
+  }
+
+  const sized: TypeToken = { ...token, size: fit.size };
+  const m = getMeasurer();
+  const family = resolveFace(token.face, rest.faceOverrides);
+  const widthOf = (s: string) =>
+    measureToken(m, sized, s, { weight: rest.weight, italic: rest.italic, family });
+  let chunks = chunkIdentifier(children, 1);
+  for (let max = children.length; max >= 1; max--) {
+    const candidate = chunkIdentifier(children, max);
+    if (candidate.every((c) => widthOf(c) <= target + 1e-6)) {
+      chunks = candidate;
+      break;
+    }
+  }
+  onFit?.({ ...fit, mode: "chunked", chunks });
+  return (
+    <View style={{ flexDirection: "row", flexWrap: "wrap", width: target, minWidth: target, maxWidth: target } as never}>
+      {chunks.map((c, i) => (
+        <Txt key={i} {...rest} align={undefined} role={sized}>
+          {c}
+        </Txt>
+      ))}
+    </View>
+  );
+}