feat(observer): v15 AG Native chat relay — scanChatBodies dual strategy (#632)

- Add AG Native DOM path: #conversation + .leading-relaxed.select-text
- Keep Cascade path: [data-testid=conversation-view] + [data-step-index]
- Register #632 in known-issues.md (SDK+DOM both blocked for AG Native)
- Bump version 0.5.50 → 0.5.51
- Add DOM analysis helper scripts

.agents/workflows/helpers/search_dom.py

@@ -0,0 +1,83 @@
+"""Search AG Native DOM dump for chat content and buttons."""
+import json, os
+
+fpath = os.path.join(os.path.expanduser('~'), '.gemini', 'antigravity', 'bridge', 'dump_html_5.json')
+with open(fpath, 'r', encoding='utf-8-sig') as f:
+    data = json.load(f)
+
+body = data.get('body', data.get('bodyTree', {}))
+qi = data.get('quickInfo', {})
+
+# Show all buttons
+print('=== BUTTONS ===')
+for b in qi.get('buttons', []):
+    print(f'  [{b["tag"]}] "{b["text"][:60]}" visible={b["visible"]} cls={b.get("cls","")[:80]}')
+
+# Data attrs
+print('\n=== DATA ATTRS ===')
+for attr in qi.get('dataAttrs', []):
+    print(f'  {attr}')
+
+# Recursive search for nodes by text
+def find_nodes_by_text(node, target, path='', results=None, depth=0):
+    if results is None: results = []
+    if not isinstance(node, dict): return results
+    tag = node.get('tag','')
+    cls = node.get('cls','')
+    text = node.get('text','')
+    children = node.get('children', [])
+    cur = f'{path}/{tag}'
+    if target.lower() in text.lower():
+        results.append({'path': cur, 'depth': depth, 'cls': cls[:80], 'text': text[:80], 'children': len(children)})
+    for c in children:
+        find_nodes_by_text(c, target, cur, results, depth+1)
+    return results
+
+print('\n=== NODES containing "Always run" ===')
+matches = find_nodes_by_text(body, 'Always run')
+for m in matches:
+    print(f'  depth={m["depth"]} cls="{m["cls"]}" text="{m["text"]}" children={m["children"]}')
+
+print('\n=== NODES containing "Always" ===')
+matches = find_nodes_by_text(body, 'Always')
+for m in matches:
+    print(f'  depth={m["depth"]} cls="{m["cls"]}" text="{m["text"]}" children={m["children"]}')
+
+# Find ALL text nodes with > 30 chars
+def find_all_text(node, results=None, depth=0, path=''):
+    if results is None: results = []
+    if not isinstance(node, dict): return results
+    tag = node.get('tag','')
+    cls = node.get('cls','')
+    text = node.get('text','')
+    children = node.get('children', [])
+    if text and len(text) > 30:
+        results.append({'depth': depth, 'tag': tag, 'cls': cls[:80], 'text': text[:100], 'path': f'{path}/{tag}'})
+    for c in children:
+        find_all_text(c, results, depth+1, f'{path}/{tag}')
+    return results
+
+print('\n=== LONG TEXT NODES (>30 chars) ===')
+texts = find_all_text(body)
+texts.sort(key=lambda x: len(x['text']), reverse=True)
+for t in texts[:25]:
+    print(f'  d={t["depth"]} [{t["tag"]}] cls="{t["cls"][:50]}" len={len(t["text"])} "{t["text"][:80]}"')
+
+# Find nodes with many children (structural containers)
+def find_containers(node, results=None, depth=0, path=''):
+    if results is None: results = []
+    if not isinstance(node, dict): return results
+    tag = node.get('tag','')
+    cls = node.get('cls','')
+    children = node.get('children', [])
+    if len(children) > 5:
+        results.append({'depth': depth, 'tag': tag, 'cls': cls[:100], 'children': len(children), 'path': f'{path}/{tag}'})
+    for c in children:
+        find_containers(c, results, depth+1, f'{path}/{tag}')
+    return results
+
+print('\n=== CONTAINERS (>5 children) ===')
+conts = find_containers(body)
+conts.sort(key=lambda x: x['children'], reverse=True)
+for c in conts[:20]:
+    print(f'  d={c["depth"]} [{c["tag"]}] children={c["children"]} cls="{c["cls"][:70]}"')