Phase 3: Skills & Context — skill system, personal context, context layering

Backend:
- Skill model + migration (with FK on chats.skill_id)
- Personal + general skill CRUD services with access isolation
- Admin skill CRUD endpoints (POST/GET/PATCH/DELETE /admin/skills)
- User skill CRUD endpoints (POST/GET/PATCH/DELETE /skills/)
- Personal context GET/PUT at /users/me/context
- Extended context assembly: primary + personal context + skill prompt
- Chat creation/update now accepts skill_id with validation

Frontend:
- Skill selector dropdown in chat header (grouped: general + personal)
- Reusable skill editor form component
- Admin skills management page (/admin/skills)
- Personal skills page (/skills)
- Personal context editor page (/profile/context)
- Updated sidebar: Skills, My Context nav items + admin skills link
- English + Russian translations for all skill/context UI

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/app/api/v1/admin.py

@@ -1,17 +1,26 @@
+import uuid
 from typing import Annotated
 
-from fastapi import APIRouter, Depends
+from fastapi import APIRouter, Depends, status
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.api.deps import require_admin
 from app.database import get_db
 from app.models.user import User
 from app.schemas.chat import ContextFileResponse, UpdateContextRequest
-from app.services import context_service
+from app.schemas.skill import (
+    CreateSkillRequest,
+    SkillListResponse,
+    SkillResponse,
+    UpdateSkillRequest,
+)
+from app.services import context_service, skill_service
 
 router = APIRouter(prefix="/admin", tags=["admin"])
 
 
+# --- Context ---
+
 @router.get("/context", response_model=ContextFileResponse | None)
 async def get_primary_context(
     _admin: Annotated[User, Depends(require_admin)],
@@ -31,3 +40,44 @@ async def update_primary_context(
 ):
     ctx = await context_service.upsert_primary_context(db, data.content, admin.id)
     return ContextFileResponse.model_validate(ctx)
+
+
+# --- Skills ---
+
+@router.get("/skills", response_model=SkillListResponse)
+async def list_general_skills(
+    _admin: Annotated[User, Depends(require_admin)],
+    db: Annotated[AsyncSession, Depends(get_db)],
+):
+    skills = await skill_service.get_general_skills(db)
+    return SkillListResponse(skills=[SkillResponse.model_validate(s) for s in skills])
+
+
+@router.post("/skills", response_model=SkillResponse, status_code=status.HTTP_201_CREATED)
+async def create_general_skill(
+    data: CreateSkillRequest,
+    _admin: Annotated[User, Depends(require_admin)],
+    db: Annotated[AsyncSession, Depends(get_db)],
+):
+    skill = await skill_service.create_general_skill(db, **data.model_dump())
+    return SkillResponse.model_validate(skill)
+
+
+@router.patch("/skills/{skill_id}", response_model=SkillResponse)
+async def update_general_skill(
+    skill_id: uuid.UUID,
+    data: UpdateSkillRequest,
+    _admin: Annotated[User, Depends(require_admin)],
+    db: Annotated[AsyncSession, Depends(get_db)],
+):
+    skill = await skill_service.update_general_skill(db, skill_id, **data.model_dump(exclude_unset=True))
+    return SkillResponse.model_validate(skill)
+
+
+@router.delete("/skills/{skill_id}", status_code=status.HTTP_204_NO_CONTENT)
+async def delete_general_skill(
+    skill_id: uuid.UUID,
+    _admin: Annotated[User, Depends(require_admin)],
+    db: Annotated[AsyncSession, Depends(get_db)],
+):
+    await skill_service.delete_general_skill(db, skill_id)