fix(dashboard,worker): vérité produit P0 — dashboard+worker+VWB export

War-room clôture DGX 2026-06-18 (recadrage Dom : graphe/apprentissage/mémoire/dashboard = surface produit P0).
Le dashboard et le statut worker affichaient des états faux ; corrige pour refléter la vérité du produit.

- dashboard FAISS: distingue index brut / metadata HMAC invalide / runtime / absent (plus de faux "inactif")
- dashboard process-mining: 503 explicite missing_dependency (plus de message trompeur)
- dashboard /api/workflows + system/status: lecture DB VWB v3 canonique (total réel = 24, plus de 0)
- worker /processing/status: véridique (lit _worker_health.json) + statut "idle/armé (lazy)" distinct de "dégradé (échec)"
- VWB export: N steps -> N actions/edges (dernière action n'est plus perdue)
- tests: dashboard routes, worker status truthfulness, export VWB

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/unit/test_dashboard_routes.py

@@ -114,6 +114,37 @@ class TestDashboardRoutes:
             'timeout': 30,
         }]
 
+    def test_streaming_status_snapshot_aggregates_existing_endpoints(self, monkeypatch):
+        """Le proxy legacy /status agrège les endpoints streaming reels."""
+        calls = []
+
+        def fake_fetch(endpoint, query_string=''):
+            calls.append((endpoint, query_string))
+            if endpoint == 'stats':
+                return {'active_sessions': 1, 'total_events': 7}
+            if endpoint == 'sessions':
+                return {'sessions': [{'session_id': 's1'}]}
+            if endpoint == 'processing/status':
+                return {'status': 'degraded', 'components_ready': False}
+            if endpoint == 'replays':
+                return {'replays': [{'replay_id': 'r1', 'active': True}]}
+            raise AssertionError(endpoint)
+
+        monkeypatch.setattr(dashboard_app, '_fetch_streaming_json', fake_fetch)
+
+        snapshot = dashboard_app._streaming_status_snapshot()
+
+        assert snapshot['active_sessions'] == 1
+        assert snapshot['sessions'] == [{'session_id': 's1'}]
+        assert snapshot['processing']['status'] == 'degraded'
+        assert snapshot['replay']['replay_id'] == 'r1'
+        assert calls == [
+            ('stats', ''),
+            ('sessions', ''),
+            ('processing/status', ''),
+            ('replays', ''),
+        ]
+
     def test_dashboard_submit_competence_verdict(self, client, monkeypatch):
         """Le dashboard journalise un verdict sans write-back YAML."""
         import core.competences.verdicts as verdicts_module
@@ -212,6 +243,58 @@ class TestDashboardRoutes:
         data = resp.get_json()
         assert 'workflows' in data
 
+    def test_workflows_list_reads_vwb_db(self, client, monkeypatch, tmp_path):
+        """Régression red-gate : /api/workflows reflète la base VWB v3, pas 0.
+
+        Avant correctif l'endpoint globait un store JSON vide et renvoyait
+        toujours total:0. On construit une DB VWB minimale (schéma canonique
+        workflows + steps) et on vérifie que l'endpoint expose le compte réel.
+        """
+        import sqlite3
+        from pathlib import Path
+
+        db_path = tmp_path / "instance" / "workflows.db"
+        db_path.parent.mkdir(parents=True, exist_ok=True)
+        conn = sqlite3.connect(str(db_path))
+        conn.execute(
+            "CREATE TABLE workflows (id VARCHAR(64) PRIMARY KEY, name VARCHAR(255), "
+            "description TEXT, created_at DATETIME, updated_at DATETIME, "
+            "is_active BOOLEAN, source VARCHAR(64), review_status VARCHAR(32))"
+        )
+        conn.execute(
+            "CREATE TABLE steps (id VARCHAR(64) PRIMARY KEY, workflow_id VARCHAR(64), "
+            "action_type VARCHAR(64))"
+        )
+        conn.execute(
+            "INSERT INTO workflows VALUES (?,?,?,?,?,?,?,?)",
+            ("wf_aiva", "Urgence_aiva_demo", "demo", "2026-06-01", "2026-06-18",
+             1, "manual", ""),
+        )
+        conn.execute(
+            "INSERT INTO workflows VALUES (?,?,?,?,?,?,?,?)",
+            ("wf_learned", "Learned_flow", "", "2026-06-02", "2026-06-17",
+             1, "learned_import", "pending"),
+        )
+        # 3 steps pour wf_aiva → nodes_count attendu = 3
+        for i in range(3):
+            conn.execute(
+                "INSERT INTO steps VALUES (?,?,?)", (f"s{i}", "wf_aiva", "click")
+            )
+        conn.commit()
+        conn.close()
+
+        monkeypatch.setattr(dashboard_app, "VWB_DB_PATH", Path(db_path))
+
+        resp = client.get('/api/workflows')
+        assert resp.status_code == 200
+        data = resp.get_json()
+        assert data['total'] == 2, f"attendu 2 workflows, obtenu {data['total']}"
+        names = {w['name'] for w in data['workflows']}
+        assert 'Urgence_aiva_demo' in names
+        aiva = next(w for w in data['workflows'] if w['name'] == 'Urgence_aiva_demo')
+        assert aiva['nodes_count'] == 3
+        assert aiva['source'] == 'manual'
+
     def test_sessions_list(self, client):
         """L'API sessions retourne la liste."""
         resp = client.get('/api/agent/sessions')