feat(agents): добавлены skills для PDF, docs, slides, jupyter и spreadsheet

- Зачем:
  - расширены возможности AI-ассистентов для работы с документами и презентациями
- Что:
  - добавлен skill pdf для работы с PDF файлами
  - добавлен skill doc для работы с Word документами
  - добавлен skill slides для создания презентаций PowerPoint
  - добавлен skill jupyter-notebook для работы с Jupyter ноутбуками
  - добавлен skill spreadsheet для работы с таблицами (Excel/CSV)
  - изменена модель Claude с sonnet на opus
- Проверка:
  - проверка доступности skills в AI-ассистентах

agents/.agents/skills/jupyter-notebook/references/tutorial-patterns.md

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+# Tutorial Patterns
+
+Use this structure for teaching and walkthroughs:
+
+- Audience, prerequisites, and learning goals: say who it is for, list what they should already know, and state what they will be able to do by the end.
+- Outline: provide a short numbered outline so readers can skim.
+- Step-by-step flow: pair a short markdown explanation with a small code cell that runs on its own and a brief interpretation of the result.
+- Exercises: include at least one exercise that reinforces the key concept and provide an answer scaffold in the next cell.
+- Pitfalls and extensions: call out one common mistake and how to fix it, and suggest one optional extension for curious readers.