phases 4-6: article system, stem note fields, edit-state cleanup

Phase 4 — remove edit-state flags from domain objects:
- ast-parser.js: drop isDirty from buildInstrument, buildBar, buildStemNote
- store.js: add resetEditState()
- PaneCP.js: use resetEditState() on import; drop flags arg from patchScore
- PaneFO.js: isDirty -> _modified for linked instruments; no per-node dirty tracking
- PaneSubObjects.js: _spliceNode helper; deletion via splice; _isNew on new bars
- exporter.js: on-demand traversal; absence from model means deleted

Phase 5 — article parser and exporter:
- ast-parser.js: _buildArticleEntry replaces _mergeArticleEntry; stage.article and
  voice.article dispatch; article properties carry scope and overwritten flag
- exporter.js: _buildArticlesBlock emits -important: list for overwrites scope

Phase 6 — stem note dead fields:
- ast-parser.js: parse weight and articulatory on stem notes; flatten
  article.definite properties onto stem note model sibling to pitch/chain

static/ast-parser.js

@@ -109,14 +109,24 @@ export function buildModel(rawTree) {
             case 'stage.cone':
                 score.stageCone = { type: 'stage_cone', ...node.props };
                 break;
-            case 'stage.voice':
-                score.stageVoices.push({
+            case 'stage.article':
+                score.articles.push(_buildArticleEntry(node));
+                break;
+            case 'stage.voice': {
+                const sv = {
                     type: 'stage_voice',
                     name: node.positionals[0],
                     direction: node.props.direction,
                     distance: node.props.distance,
-                });
+                    articles: [],
+                };
+                for (const child of node.children) {
+                    if (child.parentSlot === 'voice' && child.slot === 'article')
+                        sv.articles.push(_buildArticleEntry(child));
+                }
+                score.stageVoices.push(sv);
                 break;
+            }
             case 'instrument':
                 score.instruments.push(_buildInstrument(node));
                 break;
@@ -124,31 +134,27 @@ export function buildModel(rawTree) {
                 score.bars.push(_buildBar(node));
                 break;
             default:
-                if (node.parentSlot === 'articles') {
-                    _mergeArticleEntry(score, node);
-                } else {
-                    score[node.slot] = _buildGeneric(node);
-                }
+                score[node.slot] = _buildGeneric(node);
         }
     }
 
     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 });
+function _buildArticleEntry(node) {
+    const entry = { type: 'article', name: node.positionals[0], properties: [] };
+    for (const child of node.children) {
+        if (child.parentSlot !== 'article') continue;
+        if (child.slot === 'defaults' || child.slot === 'definite') {
+            const raw = child.props.constant ?? child.props.stacked ?? child.props.static;
+            const shapeChild = child.children.find(c => c.slot === 'shape');
+            const value = raw !== undefined ? coerce(raw) : (shapeChild ? _buildShape(shapeChild) : null);
+            entry.properties.push({ name: child.positionals[0], value, scope: child.slot, overwritten: child.props.overwritten ?? false });
+        } else if (child.slot === 'overwrites') {
+            for (const propName of child.positionals) {
+                entry.properties.push({ name: propName, value: null, scope: 'overwrites' });
+            }
+        }
     }
     return entry;
 }
@@ -176,7 +182,6 @@ function _buildInstrument(node) {
         name: node.positionals[0],
         notChangedSince: node.props.NOT_CHANGED_SINCE ?? null,
         isLinked: (node.positionals[0] ?? '').includes('/'),
-        isDirty: false,
         variations: [],
         basicProperties: null,
         volumes: null,
@@ -339,7 +344,6 @@ function _buildBar(node) {
     const bar = {
         type: 'bar',
         id: node.positionals[0] ?? '',
-        isDirty: false,
         stressor: null,
         tempoShape: null,
         tempoLevels: null,
@@ -413,7 +417,7 @@ function _buildVoice(node) {
                 voice.offsets.push(_buildOffset(child));
                 break;
             case 'voice.article':
-                voice.articles.push(child.positionals[0]);
+                voice.articles.push(_buildArticleEntry(child));
                 break;
             case 'voice.motif':
                 voice.motifs.push(_buildMotif(child));
@@ -444,9 +448,17 @@ function _buildOffset(node) {
 }
 
 function _buildStemNote(node) {
-    const KNOWN = new Set(['pitch', 'eff_length', 'adj_stress', 'adjacent']);
+    const KNOWN = new Set(['pitch', 'eff_length', 'adj_stress', 'adjacent', 'weight', 'articulatory']);
     const chainNode = node.children.find(c => c.parentSlot === 'stem_note' && c.slot === 'chain');
     const writeToNode = node.children.find(c => c.parentSlot === 'stem_note' && c.slot === 'write_to');
+    const definiteProps = {};
+    for (const child of node.children) {
+        if (child.parentSlot === 'article' && child.slot === 'definite') {
+            const raw = child.props.constant ?? child.props.stacked ?? child.props.static;
+            const shapeChild = child.children.find(c => c.slot === 'shape');
+            definiteProps[child.positionals[0]] = raw !== undefined ? coerce(raw) : (shapeChild ? _buildShape(shapeChild) : null);
+        }
+    }
     return {
         type: 'stem_note',
         pitch: node.props.pitch,
@@ -454,13 +466,13 @@ function _buildStemNote(node) {
         adjacent: node.props.adjacent ?? null,
         adjStress: node.props.adj_stress ?? null,
         length: null,
-        weight: null,
+        weight: node.props.weight ?? null,
         chainText: chainNode?.props._tmp_string ?? '',
         writeToName: writeToNode?.positionals[0] ?? null,
         clauses: (chainNode?.children ?? [])
             .filter(c => c.parentSlot === 'chain' && c.slot === 'clause')
             .map(_buildClause),
-        isDirty: false,
+        ...definiteProps,
         unknownProps: _collectUnknownProps(node.props, KNOWN),
     };
 }