Restructure project based on code owners

[matt-livefront]

🚧 Type of change

• 🎂 Other

📔 Objective

Rearranges files based on the CODEOWNERS file.

📋 Code changes

Updates the project structure to add team folders in the BitwardenShared/Core folder, which will contain the Models, Services and Repository folders (e.g. Core/Services/Auth -> Core/Auth/Services).

Also moves BitwardenShared/Application to BitwardenShared/UI/Platform/Application.

⏰ Reminders before review

• Contributor guidelines followed
• All formatters and local linters executed and passed
• Written new unit and / or integration tests where applicable
• Used internationalization (i18n) for all UI strings
• CI builds passed
• Communicated to DevOps any deployment requirements
• Updated any necessary documentation or informed the documentation team

🦮 Reviewer guidelines

• 👍 (:+1:) or similar for great changes
• 📝 (:memo:) or ℹ️ (:information_source:) for notes or general info
• ❓ (:question:) for questions
• 🤔 (:thinking:) or 💭 (:thought_balloon:) for more open inquiry that's not quite a confirmed issue and could potentially benefit from discussion
• 🎨 (:art:) for suggestions / improvements
• ❌ (:x:) or ⚠️ (:warning:) for more significant problems or concerns needing attention
• 🌱 (:seedling:) or ♻️ (:recycle:) for future improvements or indications of technical debt
• ⛏ (:pick:) for minor or nitpick changes

[nathan-livefront]

Great changes! 🚀