Articles: key by label across subtypes, scope per property, FO toggle widget

A single article label (e.g. 'f') may emit on multiple `articles.<subtype>`
lines — `defaults` today, `overwrites` planned — with disjoint property
sets that apply at different stages. Model now merges those emissions:

  { name: 'f', properties: [{ name, value, scope: 'defaults'|'overwrites' }] }

Per-label entries in the AR pane show a property-count breakdown
(`f (1 defaults, 2 overwrites)`). The Article FO pane lists each property
with a `(O-) default` / `(-O) overwrite` toggle — click flips the scope
and marks the score dirty. ASCII glyph mimics a physical switch position
so the active scope is visible at a glance.

Fixture tests cover both the existing single-subtype shape and a synthetic
two-subtype merge (177 assertions total).

static/ast-parser.js

@@ -172,7 +172,7 @@ export function buildModel(rawTree) {
                 break;
             default:
                 if (node.parentSlot === 'articles') {
-                    score.articles.push(buildArticle(node));
+                    mergeArticleEntry(score, node);
                 } else {
                     score[node.slot] = buildGeneric(node);
                 }
@@ -182,6 +182,24 @@ export function buildModel(rawTree) {
     return score;
 }
 
+// Articles are keyed by label. The AST emits one line per (label, subtype)
+// — e.g. `articles.defaults 'f'` and (future) `articles.overwrites 'f'`.
+// We merge them into one entry per label whose properties carry the scope
+// of their originating subtype, so the UI can toggle scope per property.
+function mergeArticleEntry(score, node) {
+    const name = node.positionals[0];
+    let entry = score.articles.find(a => a.name === name);
+    if (!entry) {
+        entry = { type: 'article', name, properties: [] };
+        score.articles.push(entry);
+    }
+    const scope = node.slot; // 'defaults' | 'overwrites' | future subtype
+    for (const [key, value] of Object.entries(node.props)) {
+        entry.properties.push({ name: key, value, scope });
+    }
+    return entry;
+}
+
 function buildTuning(node) {
     const t = { type: 'tuning', base: node.props.base, scales: {}, chords: {}, frequencyFactors: null };
     for (const child of node.children) {
@@ -199,15 +217,6 @@ function buildTuning(node) {
     return t;
 }
 
-function buildArticle(node) {
-    return {
-        type: 'article',
-        subtype: node.slot,
-        name: node.positionals[0],
-        props: { ...node.props },
-    };
-}
-
 function buildInstrument(node) {
     const instr = {
         type: 'instrument',

static/components/PaneFO.js

@@ -153,6 +153,29 @@ export const PaneFO = {
                         ? h(EnvelopeEditor, { basicProperties: node.basicProperties, onChange })
                         : null,
                 );
+            } else if (node.type === 'article') {
+                const markDirty = () => props.store.markDirty();
+                const SCOPES = ['defaults', 'overwrites'];
+                const scopeLabel = s => s === 'defaults' ? '(O-) default' : '(-O) overwrite';
+                children.push(
+                    h('h4', H4, `Article: ${node.name}`),
+                    h('ul', { class: 'se-article-props', style: 'list-style:none;padding:0;margin:0' },
+                        node.properties.map((p, idx) =>
+                            h('li', { key: idx, style: 'display:flex;gap:0.5rem;align-items:center;padding:0.25rem 0' }, [
+                                h('span', { style: 'flex:1' }, `${p.name} = ${p.value}`),
+                                h('button', {
+                                    class: ['se-scope-toggle', `scope-${p.scope}`],
+                                    style: 'font-family:monospace;min-width:8em',
+                                    onClick: () => {
+                                        const i = SCOPES.indexOf(p.scope);
+                                        p.scope = SCOPES[(i + 1) % SCOPES.length];
+                                        markDirty();
+                                    },
+                                }, scopeLabel(p.scope)),
+                            ])
+                        )
+                    ),
+                );
             } else if (node.type === 'bar') {
                 const markBarDirty = () => { node.isDirty = true; props.store.markDirty(); };
                 children.push(

static/subobject-kinds.js

@@ -43,9 +43,13 @@ export function getKindGroups(node) {
         }
 
         if ((node.articles ?? []).length) {
-            groups.push({ kind: 'articles', items: node.articles.map(a => ({
-                kind: 'articles', node: a, label: `${a.subtype}: ${a.name}`, hasChildren: false,
-            }))});
+            groups.push({ kind: 'articles', items: node.articles.map(a => {
+                const counts = a.properties.reduce((acc, p) => {
+                    acc[p.scope] = (acc[p.scope] ?? 0) + 1; return acc;
+                }, {});
+                const suffix = Object.entries(counts).map(([s, n]) => `${n} ${s}`).join(', ');
+                return { kind: 'articles', node: a, label: `${a.name} (${suffix})`, hasChildren: false };
+            })});
         }
 
         if (node.bars.length) {