Initial commit: RSS platform phase 1 skeleton with code review fixes

Features:
- FastAPI + SQLAlchemy 2.0 async + PostgreSQL/pgvector + Redis backend
- Vue 3 + TypeScript + Element Plus frontend
- JWT auth with access/refresh tokens and revocation
- Admin/member RBAC
- RSS feed CRUD and article listing
- Settings management with Fernet encryption for sensitive values
- Redis distributed lock service
- Alembic initial migration
- Docker Compose development environment

Fixes from code review:
- Fix DB session leak in dependency injection
- Restrict registration to admin only
- Add default admin password warning
- Implement JWT refresh tokens and jti blacklist
- Strengthen password policy
- Use func.count for pagination totals
- Replace NullPool with AsyncAdaptedQueuePool
- Remove init_db from lifespan to enforce alembic migrations
- Add request_id middleware and logging filter
- Fix vite.config.ts env loading
- Add frontend token refresh interceptor
- Add Vue error handler

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/app/schemas/user.py

@@ -0,0 +1,76 @@
+"""User Pydantic schemas."""
+import re
+
+from pydantic import BaseModel, ConfigDict, Field, field_validator
+
+_PASSWORD_RE = re.compile(r"^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d@$!%*?&_.-]{8,128}$")
+
+
+class UserBase(BaseModel):
+    """Base user schema."""
+
+    username: str = Field(..., min_length=3, max_length=64)
+    role: str = "member"
+    is_active: bool = True
+
+    @field_validator("role")
+    @classmethod
+    def _validate_role(cls, value: str) -> str:
+        allowed = {"admin", "member"}
+        if value not in allowed:
+            raise ValueError(f"role must be one of {allowed}")
+        return value
+
+
+class UserCreate(UserBase):
+    """User creation schema."""
+
+    password: str = Field(..., min_length=8, max_length=128)
+
+    @field_validator("password")
+    @classmethod
+    def _validate_password_strength(cls, value: str) -> str:
+        if not _PASSWORD_RE.match(value):
+            raise ValueError(
+                "password must be 8-128 characters and contain at least one letter and one number"
+            )
+        return value
+
+
+class UserOut(UserBase):
+    """User output schema."""
+
+    model_config = ConfigDict(from_attributes=True)
+
+    id: str
+
+
+class UserLogin(BaseModel):
+    """User login schema."""
+
+    username: str
+    password: str
+
+
+class TokenResponse(BaseModel):
+    """Token response schema."""
+
+    access_token: str
+    refresh_token: str
+    token_type: str = "bearer"
+
+
+class TokenPayload(BaseModel):
+    """JWT token payload."""
+
+    sub: str | None = None
+    role: str | None = None
+    jti: str | None = None
+    type: str | None = None
+    exp: int | None = None
+
+
+class RefreshTokenRequest(BaseModel):
+    """Refresh token request schema."""
+
+    refresh_token: str