Bold renders the real element: the Bold color setting applies

The owner's repro: the appearance Bold color never applied anywhere.
Root cause: streamdown's default `strong` component renders bold as
<span class="font-semibold" data-streamdown="strong"> - NOT a
<strong> element - while the app's ink plumbing (.lh-prose
:where(strong, b) in globals.css, zero specificity by design) matches
strong/b ELEMENTS. So bold text never took --lh-ink-strong: not the
factory #c96b4a, not any settings boldColor (it rendered plain
foreground at weight 600). Italic always worked because streamdown
leaves `em` native - hence the asymmetry the owner noticed.

Fix: a `strong` override in mdComponents (the stable module-level set,
so Streamdown's memoized tree keeps identity) renders the semantic
element: <strong data-streamdown="strong">. Screen readers announce
emphasis again, the designed token rule applies unmodified, and the
weight reads 700 (the .lh-prose rule) instead of the span's 600.

Both Streamdown surfaces (MessageResponse, reasoning) pass
mdComponents, so every markdown surface is covered.

Verified live: bold in seedplan now renders #c96b4a at weight 700 in a
real <strong>; after PUTting boldColor #7dd3fc the live strong flips
to rgb(125,211,252) with no reload; italic unchanged (#6fa9d6 native
em). Scratch record restored to unset.

components/md-blocks.tsx

@@ -338,8 +338,26 @@ export function MathDisplay(props: ComponentProps<"span"> & ExtraProps) {
 
 // ─── The stable override set (module identity: Streamdown is memoized) ────────
 
+/** Bold as the REAL element (appearance fix, 2026-09-23): streamdown's
+ *  default `strong` renders `<span class="font-semibold" data-streamdown=
+ *  "strong">` — and `.lh-prose :where(strong, b)` matches strong/b
+ *  ELEMENTS, so neither the factory ink (#c96b4a) nor a settings
+ *  boldColor ever landed on bold text (italic worked: streamdown leaves
+ *  `em` native). Rendering the semantic element restores screen-reader
+ *  emphasis AND lets the designed token rule apply unmodified — color
+ *  --lh-ink-strong, weight 700 (beating the old 600 utility). */
+export function MarkdownStrong(props: ComponentProps<"strong"> & ExtraProps) {
+	const { children, className, node, ...rest } = props;
+	return (
+		<strong data-streamdown="strong" className={className} {...rest}>
+			{children}
+		</strong>
+	);
+}
+
 export const mdComponents = {
 	code: MarkdownCode,
 	table: MarkdownTable,
 	span: MathDisplay,
+	strong: MarkdownStrong,
 };

tests/render-markdown.test.tsx

@@ -212,3 +212,31 @@ describe("render — mermaid", () => {
 		assert.match(html, />Retry</);
 	});
 });
+
+
+describe("render — bold is the real <strong> (the dead Bold-color fix)", () => {
+	// Streamdown's default `strong` renders <span class="font-semibold"
+	// data-streamdown="strong"> — and the app's ink token rule
+	// (.lh-prose :where(strong, b), globals.css) matches strong/b
+	// ELEMENTS, so bold never took the --lh-ink-strong color (neither the
+	// factory #c96b4a nor a settings boldColor). The mdComponents override
+	// renders the semantic element.
+	it("bold renders a real <strong> element inside .lh-prose", () => {
+		const html = render("plain **bold** plain");
+		assert.ok(
+			html.includes('<strong data-streamdown="strong">bold</strong>'),
+			"bold renders as a semantic strong element",
+		);
+		assert.ok(html.includes("lh-prose"), "the markdown surface carries .lh-prose (the token rule's anchor)");
+	});
+
+	it("no span-for-bold regression: the font-semibold span is gone", () => {
+		const html = render("plain **bold** plain");
+		assert.ok(!html.includes('class="font-semibold"'), "streamdown's span/600 default must not render bold");
+	});
+
+	it("italic stays native <em> (the case that always worked)", () => {
+		const html = render("plain *emph* plain");
+		assert.ok(html.includes("<em>"), "italic renders a native em element");
+	});
+});