merge(dev): integrate latest upstream dev (PR #6840 sidebar animations)

- Merge upstream/dev at 0116f0a62b
- Incorporate upstream sidebar toggle animation and auto-collapse measurement fixes
- Preserve upstream CSS snapshot baseline in tests/css_snapshot/baseline.json
- Retain all PR #6741 photo-editor features, security controls, and mobile fixes

tests/css_snapshot/baseline.json

@@ -1,5 +1,5 @@
 {
- "digest": "f7e60e4a567c46dc",
+ "digest": "5282a075729cc246",
  "elements": {
   "app-shell": {
    "app-loader": "f04ad5bf6312d53f",
@@ -17,7 +17,7 @@
    "export-dropdown-item": "d90f6f513d06a6f7",
    "export-dropdown-menu": "0793e06a6aae6a7a",
    "hamburger-btn": "34714f6eef3734d8",
-   "icon-rail": "e3f72205260a4a5f",
+   "icon-rail": "c800b4ef07f5f1f0",
    "icon-rail-btn": "54ffb10e056ebf44",
    "incognito-btn": "ee42bd3f6a32576b",
    "input-icon-btn": "3d1c773acd84a825",
@@ -59,7 +59,7 @@
    "settings-row": "de568724268cec6e",
    "settings-select": "a96e8430b0ec6668",
    "settings-sidebar-toggle": "6be9025ab24bc434",
-   "sidebar": "77ec42a646a8db66",
+   "sidebar": "0dbf510da61afa07",
    "sidebar-brand": "d3d7ef4b21514e80",
    "sidebar-new-chat": "567fae30048b7ff3",
    "sidebar-resize-handle": "6607b819ee45409d",
@@ -488,7 +488,7 @@
    ".hwfit-serve-topline .hwfit-serve-runtime-note": "15b3fef4e5ceaffc",
    ".hwfit-serve-topline .hwfit-serve-runtime-text": "57c6822b0d13147d",
    ".hwfit-spec-group .hwfit-spec-method": "5d1c329116272cf1",
-   ".icon-rail": "e3f72205260a4a5f",
+   ".icon-rail": "c800b4ef07f5f1f0",
    ".icon-rail-btn": "a5f207c3be15401e",
    ".incognito-btn": "9833a2e86fab6a94",
    ".incognito-indicator": "b3945c46844c7278",
@@ -617,15 +617,15 @@
    ".settings-sidebar.settings-sidebar-collapsed": "d9d8f25df95d9ad8",
    ".settings-sidebar.settings-sidebar-collapsed .settings-sidebar-content": "608e51170864586a",
    ".settings-system-logs-tab": "d0d90a13ff327ace",
-   ".sidebar": "77ec42a646a8db66",
+   ".sidebar": "0dbf510da61afa07",
    ".sidebar .section": "37fc733d59519a08",
    ".sidebar-brand-title": "2b20f75768b50346",
    ".sidebar-header": "0d58816ca65b7216",
    ".sidebar-inner": "ad5e28fedbfeb5db",
    ".sidebar-notif-dot": "2673e215d0cd84a6",
    ".sidebar-user-bar": "b77372dbdcb069ef",
-   ".sidebar.hidden": "0df301b638e2f93f",
-   ".sidebar.right-side": "2b6bcc7d59f7b6bd",
+   ".sidebar.hidden": "9021ec7e4e052131",
+   ".sidebar.right-side": "bb6ed4427d07657e",
    ".skill-card > .skill-card-header": "e2408e762818d2fb",
    ".skill-card-tags": "a327c85e053e6d3f",
    ".skill-card-textcol": "f1059ed37c120b60",
@@ -686,56 +686,56 @@
  },
  "variants": {
   "app-shell": {
-   "desktop-dark-comfortable": "0c9123117135e362",
-   "desktop-dark-compact": "c694f5d5118ac0e2",
-   "desktop-dark-spacious": "90a67613e8cfdf5d",
-   "desktop-light-comfortable": "17727a9945ccc77b",
-   "desktop-light-compact": "2a887c30d231e357",
-   "desktop-light-spacious": "94b4666734b87625",
-   "laptop-dark-comfortable": "26d334b139b653f2",
-   "laptop-dark-compact": "fea30bad6824357d",
-   "laptop-dark-spacious": "4fdb28deaaaec870",
-   "laptop-light-comfortable": "c7fc986a7e70aac8",
-   "laptop-light-compact": "147645431229ddff",
-   "laptop-light-spacious": "d513c285d30c8289",
-   "phone-dark-comfortable": "551761344bec8d09",
-   "phone-dark-compact": "293d66518c3ec994",
-   "phone-dark-spacious": "551761344bec8d09",
-   "phone-light-comfortable": "cb41acd3f9af3578",
-   "phone-light-compact": "dbef6e9e373e9c10",
-   "phone-light-spacious": "cb41acd3f9af3578",
-   "tablet-dark-comfortable": "0f682621b4ead393",
-   "tablet-dark-compact": "e6f3fece5e716a2c",
-   "tablet-dark-spacious": "0f682621b4ead393",
-   "tablet-light-comfortable": "6e398df9ca69c58b",
-   "tablet-light-compact": "dca75981c8675bfa",
-   "tablet-light-spacious": "6e398df9ca69c58b"
+   "desktop-dark-comfortable": "a401d90436a5ca64",
+   "desktop-dark-compact": "207348542b2e4e0f",
+   "desktop-dark-spacious": "cf93e41d494c2fdc",
+   "desktop-light-comfortable": "e080e0286a12ad19",
+   "desktop-light-compact": "5ecb27fdc079e051",
+   "desktop-light-spacious": "97eeb23477e3ac77",
+   "laptop-dark-comfortable": "c3142729689b9c36",
+   "laptop-dark-compact": "2d0bd3f5e3075c14",
+   "laptop-dark-spacious": "4c9a7ddc3fa236e4",
+   "laptop-light-comfortable": "234d92df9bed6f4c",
+   "laptop-light-compact": "a619f09b8b9e33e5",
+   "laptop-light-spacious": "5dea4413f33a9002",
+   "phone-dark-comfortable": "86f8033e0a23b873",
+   "phone-dark-compact": "2df6fce436ebbaac",
+   "phone-dark-spacious": "86f8033e0a23b873",
+   "phone-light-comfortable": "0067d466b77774f5",
+   "phone-light-compact": "8c82bcc55dd57b63",
+   "phone-light-spacious": "0067d466b77774f5",
+   "tablet-dark-comfortable": "dfeed4c65fea98a1",
+   "tablet-dark-compact": "cbdb84a6edc362bf",
+   "tablet-dark-spacious": "dfeed4c65fea98a1",
+   "tablet-light-comfortable": "7399146b3d437f7f",
+   "tablet-light-compact": "be6bf69a5215b052",
+   "tablet-light-spacious": "7399146b3d437f7f"
   },
   "bench": {
-   "desktop-dark-comfortable": "a9709cb47eec7544",
-   "desktop-dark-compact": "bfab96cb72fd6faf",
-   "desktop-dark-spacious": "25469178b443428a",
-   "desktop-light-comfortable": "2166794d643fae4c",
-   "desktop-light-compact": "81d8ab64407b1d9a",
-   "desktop-light-spacious": "d6d19f33476665af",
-   "laptop-dark-comfortable": "57169e64e1fb5324",
-   "laptop-dark-compact": "6ac903cd8a711bcf",
-   "laptop-dark-spacious": "a47535332e9c5de7",
-   "laptop-light-comfortable": "1e2b381de3556fac",
-   "laptop-light-compact": "6dbfb465121949c1",
-   "laptop-light-spacious": "1b8bfcd4bc4ed214",
-   "phone-dark-comfortable": "67ca3c78e6b9495a",
-   "phone-dark-compact": "ad6f3a9f5c8d81cd",
-   "phone-dark-spacious": "1e6f66e56519ba5d",
-   "phone-light-comfortable": "ef876073cc2dc45e",
-   "phone-light-compact": "2ef6f5dc7a646be9",
-   "phone-light-spacious": "b0d4cd9bd0361966",
-   "tablet-dark-comfortable": "58922240b216e786",
-   "tablet-dark-compact": "3991c22f99a394e0",
-   "tablet-dark-spacious": "9848c3b7debac974",
-   "tablet-light-comfortable": "12dfbad36172de20",
-   "tablet-light-compact": "80d4843e622f1353",
-   "tablet-light-spacious": "c420b8d46c991a44"
+   "desktop-dark-comfortable": "477394268d56dab4",
+   "desktop-dark-compact": "cdb2a994f2347d9a",
+   "desktop-dark-spacious": "44a0286474f509bc",
+   "desktop-light-comfortable": "b4991b72e1629a7e",
+   "desktop-light-compact": "4b31438b6cf29191",
+   "desktop-light-spacious": "6d2bb1699acb8ba1",
+   "laptop-dark-comfortable": "6b8df96c7323bd57",
+   "laptop-dark-compact": "9af052dd3ee47593",
+   "laptop-dark-spacious": "7d031596ee98a11f",
+   "laptop-light-comfortable": "352a8564ecebd3dd",
+   "laptop-light-compact": "c038f51edaf78a6b",
+   "laptop-light-spacious": "232cfb9c427a156d",
+   "phone-dark-comfortable": "1f66ccc3d46e3d59",
+   "phone-dark-compact": "14802a927af47d2a",
+   "phone-dark-spacious": "3b48b91c9f218777",
+   "phone-light-comfortable": "191dd9704ea10245",
+   "phone-light-compact": "2f659a85548fd8d6",
+   "phone-light-spacious": "ece925a707889ec4",
+   "tablet-dark-comfortable": "7075293d10d618b5",
+   "tablet-dark-compact": "792f8efb8de95a25",
+   "tablet-dark-spacious": "b7ec70ad523b5a2e",
+   "tablet-light-comfortable": "bdf9d78bf3cd5ced",
+   "tablet-light-compact": "990bb4d23e0fbac9",
+   "tablet-light-spacious": "53c5142d2fca6fc1"
   },
   "login": {
    "desktop-dark-comfortable": "3cf4809db0f8e119",