feat(auth): support trusted device (#52)

New API to maintain sessions and devices:

- GET /api/private/admin/sessions
- DELETE /api/private/admin/sessions/{session_id}
- GET /api/private/admin/trusted-devices
- DELETE /api/private/admin/trusted-devices/{device_id}

Auth:

web clients request `/oauth/token` and `/api/v2/session/verify` with `X-UUID` header to save the client as trusted device.

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

app/models/model.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+from dataclasses import dataclass
 from datetime import UTC, datetime
 
 from app.models.score import GameMode
@@ -53,3 +54,33 @@ class CurrentUserAttributes(BaseModel):
     can_new_comment: bool | None = None
     can_new_comment_reason: str | None = None
     pin: PinAttributes | None = None
+
+
+@dataclass
+class UserAgentInfo:
+    raw_ua: str = ""
+    browser: str | None = None
+    version: str | None = None
+    os: str | None = None
+    platform: str | None = None
+    is_mobile: bool = False
+    is_tablet: bool = False
+    is_pc: bool = False
+    is_client: bool = False
+
+    @property
+    def displayed_name(self) -> str:
+        parts = []
+        if self.browser:
+            parts.append(self.browser)
+            if self.version:
+                parts.append(self.version)
+        if self.os:
+            if parts:
+                parts.append(f"on {self.os}")
+            else:
+                parts.append(self.os)
+        return " ".join(parts) if parts else "Unknown"
+
+    def __str__(self) -> str:
+        return self.displayed_name