Added ability to tag saved conversations

[logicsec]

Purpose
This pull request adds the ability to tag conversations within Obsidian Copilot, allowing for easier referencing and analysis using Dataview.

Motivation:
Currently, Obsidian Copilot doesn't offer a way to tag conversations, making it difficult to organize and retrieve specific conversations for analysis using Dataview.

This feature would enable users to:

• Categorize conversations: Tag conversations based on topics, projects, or other relevant criteria.
• Filter conversations: Use Dataview queries to retrieve conversations based on specific tags.
• Analyze conversations: Gain insights from tagged conversations by using Dataview's powerful analysis capabilities.

Changes:

• Added a new settings called Default Conversation Tag which defaults to ai-conversation.
• Updated SettingsPage.tsc CopilotSettings interface to reference the new defaultTag string
• Updated Chat.tsx to reference the new setting
• Updated GeneralSettings.tsx to include new TextComponent

[logancyang]

How about defaultConversationTag and put it below the defaultSaveFolder below

[logancyang]

I don't see where you set the default ai-conversations though, it's in constants.ts

[logancyang]

Thanks for the PR. Added some comments.

[logicsec]

Fixing these now. Should have it shortly.

[logicsec]

Updated. I think for now, 1 tag should be ok. In the future, we should take a look at ability to do tag lookups and allow for multi-select.