Generalize from health-specific to universal personal assistant

The app manages multiple life areas (health, finance, personal, work),
not just health. Updated all health-specific language throughout:

Backend:
- Default system prompt: general personal assistant (not health-only)
- AI tool descriptions: generic (not health records/medications)
- Memory categories: health, finance, personal, work, document_summary, other
  (replaces condition, medication, allergy, vital)
- PDF template: "Prepared for" (not "Patient"), "Key Information" (not "Health Profile")
- Renamed generate_health_pdf -> generate_pdf_report, health_report.html -> report.html
- Renamed run_daily_health_review -> run_daily_review
- Context assembly: "User Profile" (not "Health Profile")
- OpenAPI: generic descriptions

Frontend:
- Dashboard subtitle: "Your personal AI assistant"
- Memory categories: Health, Finance, Personal, Work
- Document types: Report, Contract, Receipt, Certificate (not lab_result, etc.)
- Updated en + ru translations throughout

Documentation:
- README: general personal assistant description
- Removed health-only feature descriptions

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

backend/app/api/v1/pdf.py

@@ -21,7 +21,7 @@ async def compile_pdf(
     user: Annotated[User, Depends(get_current_user)],
     db: Annotated[AsyncSession, Depends(get_db)],
 ):
-    pdf = await pdf_service.generate_health_pdf(
+    pdf = await pdf_service.generate_pdf_report(
         db, user.id, data.title, data.document_ids or None, data.chat_id,
     )
     return PdfResponse.model_validate(pdf)