feat: #78 Excalidraw finitions + #67 push + #68 health-detailed + #77 desktop jumplist

#78 Excalidraw — finitions B5/C8/F2/F3
- backend/indexer.py: port Python pur de lz-string decompressFromBase64 (bitsPerChar=6, resetValue=32) validé contre 4 fixtures JS truth (texte accentué, edge cases) — remplace le stub base64 non-fonctionnel
- B5 indexation: .excalidraw.md (format plugin Obsidian) maintenant décompressé côté Python → texte indexé pour recherche TF-IDF
- 7 nouveaux tests B5 dans tests/test_excalidraw.py (13/13 total)
- F2: excalidraw-viewer.test.mjs enregistré dans CI (lint job)
- F3: tests/e2e/excalidraw.spec.js (9 specs — ouverture .excalidraw/.excalidraw.md, création via modale/menu contextuel, toolbar, thème, pop-out, recherche)
- Fixtures test_vault/diagram.excalidraw + diagram.excalidraw.md

#67 Push notifications (Web Push API + VAPID)
- backend/push.py: router + VAPID keys + send_push_notification (pywebpush>=2.3.0)
- frontend/js/push.js: subscription UI + service worker integration
- tests/test_push.py: 10 tests (subscribe/list/unsubscribe/vapid key)
- requirements.txt + sw.js + locales push strings

#68 Health check enrichi
- backend/main.py: GET /api/health/detailed (admin) — memory/cpu/disk/backups/index/SSE connections
- backend/indexer.py: _last_full_index_ts tracking
- tests/conftest.py: admin_client fixture
- tests/test_api_main.py: 3 nouveaux tests health detailed

#77 Desktop jumplist
- desktop/src/jumplist.rs: Windows jumplist integration
- Cargo.toml/lock + capabilities + main.rs
- frontend/js/desktop.js: Tauri bridge (isTauriEnv, invoke, getSystemTheme, syncSystemTheme, shouldShowWizard, crash banner)
- tests/frontend/desktop.test.mjs: 21 tests JSDOM (détection, invoke degradation, theme gating, wizard, crash banner)
- tests/frontend/unit.test.mjs: desktop.js whitelisted (standalone global reader)

# Frontend & CI
- frontend/sw.js: réécriture complète (precache + push event handlers + offline)
- frontend/index.html: section push dans settings + about repositionné
- frontend/js/app.js: initDesktopIntegration + initPush
- CI .gitea/workflows/ci.yml: excalidraw-viewer.test.mjs ajouté au lint job

All checks: ruff clean, 552 backend tests pass, 9 frontend unit, 5 excalidraw-viewer, 21 desktop, 9 pane-manager, validate-imports 33 modules.

tests/test_excalidraw.py

@@ -2,7 +2,6 @@
 
 import json
 
-
 EXCALIDRAW_SKELETON = {
     "type": "excalidraw",
     "version": 2,
@@ -47,6 +46,34 @@ EXCALIDRAW_WITH_CONTENT = {
     "files": {},
 }
 
+# ████████████████████████████████████████████████████████████████████████
+# B5 — Indexation du contenu texte Excalidraw (recherche TF-IDF)
+# ████████████████████████████████████████████████████████████████████████
+# Fixture lz-string "compressToBase64" générée par le vrai paquet
+# [email protected] (JS) en 2026-09-09, validée byte-pour-byte contre le port
+# Python de `_decompress_excalidraw`. Contient du texte accentué.
+LZ_COMPRESSED_DIAGRAM = (
+    "N4IgLgngDgpiBcIYA8DGBDANgSwCYCd0B3EAGhADcZ8BnbAewDsEAmcmTGAWxkbBoQBtUHgQh0"
+    "ZcNDiIwKMJLnIFiABIdM9AAQBRNFjyES5evmwBzbIywAVeWPWZNu/TgLFJyBAEYADOQhWXwBf"
+    "UhFcMQAjRWkxJQVyeLEAJQBLmgBXLlStOVQAC0ZsAEcMmC0AMi1GejkBEzNLa0w7ZRT0rJy8"
+    "wpKyyuramHqQL3gAZn8QQPgAFhCwkFFEVBjYMXwYVDB0RnNOSUx0SI4xACF6ADu5LWwuKF"
+    "NtvjhyUYBWAIRX4IBdcnQoKAAZW2cgQoGsPDEABEhnRmKEQAAzbCcATwYDBYJAA"
+)
+
+_RAW_EXCALIDRAW_MD = """---
+excalidraw-plugin: parsed
+---
+```compressed-json
+{comp}
+```
+
+Ce texte hors bloc ne doit pas polluer l'index (on extrait la scène uniquement).
+"""
+
+
+def _make_excalidraw_md(compressed: str) -> str:
+    return _RAW_EXCALIDRAW_MD.format(comp=compressed)
+
 
 class TestExcalidrawDetection:
     """Test that the /api/file endpoint correctly detects .excalidraw files."""
@@ -164,3 +191,71 @@ class TestExcalidrawDetection:
         assert data["is_excalidraw"] is True
         assert len(data["excalidraw_data"]["elements"]) == 1
         assert data["excalidraw_data"]["elements"][0]["type"] == "ellipse"
+
+
+class TestExcalidrawIndexableTextB5:
+    """B5 — Indexation du texte des éléments (recherche TF-IDF)."""
+
+    def test_pure_json_extracts_element_text(self):
+        from backend.indexer import extract_excalidraw_indexable
+
+        out = extract_excalidraw_indexable(json.dumps(EXCALIDRAW_WITH_CONTENT))
+        assert "Hello Excalidraw" in out
+
+    def test_pure_json_skeleton_has_no_text(self):
+        from backend.indexer import extract_excalidraw_indexable
+
+        out = extract_excalidraw_indexable(json.dumps(EXCALIDRAW_SKELETON))
+        assert out.strip() == ""
+
+    def test_pure_json_binds_label_and_title(self):
+        from backend.indexer import extract_excalidraw_indexable
+
+        payload = {
+            "type": "excalidraw",
+            "version": 2,
+            "elements": [
+                {"id": "r", "type": "rectangle", "label": "Boite bleue"},
+                {"id": "t", "type": "text", "text": "texte simple",
+                 "originalText": "texte simple"},
+            ],
+            "appState": {},
+            "files": {},
+        }
+        out = extract_excalidraw_indexable(json.dumps(payload))
+        assert "Boite bleue" in out
+        assert "texte simple" in out
+
+    def test_lz_decompress_matches_js_fixture(self):
+        """Le port Python décode un payload lz-string produit par le vrai JS."""
+        from backend.indexer import _decompress_excalidraw
+
+        data = _decompress_excalidraw(LZ_COMPRESSED_DIAGRAM)
+        assert data is not None
+        assert data["type"] == "excalidraw"
+        elements = data["elements"]
+        texts = {e.get("text") or e.get("label") for e in elements if isinstance(e, dict)}
+        assert "Hello Excalidraw" in texts
+        assert "Résumé technique & notes" in texts
+        assert "Boîte importante" in texts
+
+    def test_lz_decompress_rejects_garbage(self):
+        from backend.indexer import _decompress_excalidraw
+
+        assert _decompress_excalidraw("") is None
+        assert _decompress_excalidraw("@@@not-lz@@@") is None
+        assert _decompress_excalidraw("!!!") is None
+
+    def test_excalidraw_md_compressed_extracts_text(self):
+        """.excalidraw.md (format plugin Obsidian) → texte indexé."""
+        from backend.indexer import extract_excalidraw_indexable
+
+        out = extract_excalidraw_indexable(_make_excalidraw_md(LZ_COMPRESSED_DIAGRAM))
+        assert "Hello Excalidraw" in out
+        assert "Boîte importante" in out
+
+    def test_excalidraw_md_missing_block_returns_empty(self):
+        from backend.indexer import extract_excalidraw_indexable
+
+        out = extract_excalidraw_indexable("---\nexcalidraw-plugin: parsed\n---\n(pas de bloc)")
+        assert out.strip() == ""