feat: add user creation form in admin panel

app/admin/router.py

@@ -1,7 +1,7 @@
 from jinja2 import Environment, FileSystemLoader
 
-from fastapi import APIRouter, Request
-from fastapi.responses import HTMLResponse
+from fastapi import APIRouter, Form, Request
+from fastapi.responses import HTMLResponse, RedirectResponse
 from sqlalchemy import func, select
 
 from app.database import async_session_factory
@@ -13,6 +13,7 @@ from app.repositories.payment import PaymentRepository
 from app.repositories.server import ServerRepository
 from app.repositories.tariff import TariffRepository
 from app.repositories.user import UserRepository
+from app.services.user import UserService
 
 router = APIRouter(prefix="/admin", tags=["admin"])
 
@@ -66,16 +67,49 @@ async def dashboard(request: Request):
 
 
 @router.get("/users", response_class=HTMLResponse)
-async def users_page(request: Request):
+async def users_page(request: Request, error: str = ""):
     async with async_session_factory() as session:
         repo = UserRepository(session)
         users = await repo.get_all()
 
     return HTMLResponse(
-        _render("users.html", request=request, users=users)
+        _render("users.html", request=request, users=users, error=error)
     )
 
 
+@router.post("/users/create", response_class=HTMLResponse)
+async def users_create(
+    request: Request,
+    telegram_id: int = Form(...),
+    username: str = Form(""),
+    full_name: str = Form(""),
+    language_code: str = Form("ru"),
+):
+    async with async_session_factory() as session:
+        user_repo = UserRepository(session)
+        user_service = UserService(user_repo)
+
+        existing = await user_repo.get_by_telegram_id(telegram_id)
+        if existing is not None:
+            return HTMLResponse(
+                _render(
+                    "users.html",
+                    request=request,
+                    users=await user_repo.get_all(),
+                    error=f"User with telegram_id {telegram_id} already exists",
+                )
+            )
+
+        await user_service.register(
+            telegram_id=telegram_id,
+            username=username or None,
+            full_name=full_name or str(telegram_id),
+            language_code=language_code,
+        )
+
+    return RedirectResponse(url="/admin/users", status_code=303)
+
+
 @router.get("/payments", response_class=HTMLResponse)
 async def payments_page(request: Request):
     async with async_session_factory() as session: