feat(photo-editor): NL editor planner, image ops, email/gallery server

Server-side photo editor: natural-language editor agent route
(/api/editor/agent), photo_editor tool family + style guide, image-op
provider proxy with progress, email server hardening, gallery/hwfit
routes, and graceful shutdown.

Source: vendor/photocraft (ad1cff44) editor-server files, merged onto
upstream/dev (a8c147b2). Conflict resolution documented in
pr_work/B_conflicts.md.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/test_gallery_image_endpoint_fallback.py

@@ -0,0 +1,124 @@
+"""Image endpoint fallback: image models on mixed (non image-only) endpoints.
+
+Chat image generation resolves its model by name across every enabled endpoint,
+so a ``qwen-image-edit`` / ``gpt-image-1`` model registered on a shared
+OpenAI-compatible gateway works there. The editor's generative ops used a
+stricter image-only lookup and reported "No image generation endpoint
+configured" on those same setups. These tests pin the fallback that makes the
+editor find the same endpoint.
+"""
+
+from types import SimpleNamespace
+
+import routes.gallery_routes as gallery_routes
+
+
+class _Predicate:
+    def __init__(self, check):
+        self._check = check
+
+    def __call__(self, row):
+        return self._check(row)
+
+    def __or__(self, other):
+        return _Predicate(lambda row: self(row) or other(row))
+
+
+class _Column:
+    def __init__(self, name):
+        self.name = name
+
+    def __eq__(self, value):
+        return _Predicate(lambda row: getattr(row, self.name) == value)
+
+
+class _ModelEndpoint:
+    base_url = _Column("base_url")
+    model_type = _Column("model_type")
+    is_enabled = _Column("is_enabled")
+    owner = _Column("owner")
+
+
+class _Query:
+    def __init__(self, rows):
+        self._rows = list(rows)
+
+    def filter(self, *predicates):
+        self._rows = [row for row in self._rows if all(pred(row) for pred in predicates)]
+        return self
+
+    def all(self):
+        return list(self._rows)
+
+
+class _DB:
+    def __init__(self, rows):
+        self._rows = rows
+
+    def query(self, model):
+        assert model is _ModelEndpoint
+        return _Query(self._rows)
+
+
+def _ep(base_url, owner=None, *, enabled=True, model_type="chat", models=None):
+    return SimpleNamespace(
+        base_url=base_url,
+        owner=owner,
+        is_enabled=enabled,
+        model_type=model_type,
+        api_key="sk-secret",
+        cached_models=models or [],
+        pinned_models=[],
+    )
+
+
+def _patch_model(monkeypatch):
+    monkeypatch.setattr(gallery_routes, "ModelEndpoint", _ModelEndpoint)
+
+
+def test_mixed_endpoint_with_image_model_is_found(monkeypatch):
+    _patch_model(monkeypatch)
+    rows = [_ep("https://gateway.example.com/v1", models=["qwen-image-edit", "llama-3"])]
+
+    ep = gallery_routes._first_visible_image_endpoint(_DB(rows), None)
+
+    assert ep is not None
+    assert ep.base_url == "https://gateway.example.com/v1"
+
+
+def test_mixed_endpoint_without_image_model_is_ignored(monkeypatch):
+    _patch_model(monkeypatch)
+    rows = [_ep("https://gateway.example.com/v1", models=["llama-3", "mistral"])]
+
+    assert gallery_routes._first_visible_image_endpoint(_DB(rows), None) is None
+
+
+def test_image_only_endpoint_wins_over_mixed(monkeypatch):
+    _patch_model(monkeypatch)
+    rows = [
+        _ep("https://gateway.example.com/v1", models=["gpt-image-1"]),
+        _ep("https://images.example.com/v1", model_type="image"),
+    ]
+
+    ep = gallery_routes._first_visible_image_endpoint(_DB(rows), None)
+
+    assert ep is not None
+    assert ep.model_type == "image"
+
+
+def test_unreachable_endpoint_reports_502():
+    """The inpaint proxy must distinguish an unreachable endpoint from a provider error.
+
+    502 (gateway) is reserved for "the image server could not be reached"; 503 is
+    reserved for "generation is switched off on the server", which the editor maps
+    to its own fixed message.
+    """
+    from pathlib import Path
+
+    src = (
+        Path(__file__).resolve().parents[1] / "routes" / "gallery" / "gallery_routes.py"
+    ).read_text()
+    assert "Image server unreachable" in src
+    assert "except httpx.TransportError as exc:" in src
+    assert "provider HTTP" in src
+    assert 'raise HTTPException(503, f"Image endpoint unreachable' not in src