feat: add config read API (GET /api/0/config, /section/{name}, /backups)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/test_http_config_api.py

@@ -0,0 +1,49 @@
+"""Tests for the config read/write API helpers in http.py."""
+import pytest
+from hbd.server import http
+
+
+def test_mask_config_for_api_masks_user_passwords():
+    config = {
+        "hbd_port": 50004,
+        "interval": 20,
+        "users": {
+            "alice": {"full_name": "Alice", "admin": True, "password": "pbkdf2:sha256:abc"},
+        },
+        "oauth": {},
+    }
+    result = http._mask_config_for_api(config)
+    assert result["users"]["alice"]["password"] == "•••"
+    assert result["users"]["alice"]["full_name"] == "Alice"
+
+
+def test_mask_config_for_api_masks_oauth_client_secret():
+    config = {
+        "hbd_port": 50004,
+        "interval": 20,
+        "users": {},
+        "oauth": {
+            "gitea": {"type": "gitea", "url": "https://git.example.com",
+                      "client_id": "cid", "client_secret": "verysecret"},
+        },
+    }
+    result = http._mask_config_for_api(config)
+    assert result["oauth"]["gitea"]["client_secret"] == "•••"
+    assert result["oauth"]["gitea"]["client_id"] == "cid"
+
+
+def test_mask_config_for_api_includes_server_keys():
+    config = {"hbd_port": 50004, "interval": 20, "users": {}, "oauth": {}}
+    result = http._mask_config_for_api(config)
+    assert result["server"]["hbd_port"] == 50004
+    assert result["server"]["interval"] == 20
+
+
+def test_mask_config_for_api_no_password_in_users_leaves_no_key():
+    config = {
+        "hbd_port": 50004,
+        "users": {"bob": {"full_name": "Bob", "admin": False}},
+        "oauth": {},
+    }
+    result = http._mask_config_for_api(config)
+    assert "password" not in result["users"]["bob"]