feature: command to export conversation in markdown

[spinualexandru]

Brief description of what this PR does

• Adds the ability to export the conversation as markdown, solves Feature Request: Add /export command to export chat history to markdown #6

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation update

Testing

• Tested with Ollama
• Tested with OpenRouter
• Tested with OpenAI-compatible API
• Tested MCP integration (if applicable)

Checklist

• Code follows project style guidelines
• Self-review completed
• Documentation updated (if needed)
• No breaking changes (or clearly documented)

[Copilot]

Pull Request Overview

This PR adds the ability to export conversation history to markdown files, addressing issue #6. The export command creates markdown files with metadata frontmatter including session date, provider, model, and total tokens.

• Extends the Command interface to accept messages and metadata parameters
• Updates all existing commands to match the new interface signature
• Adds a new /export command that generates markdown files with conversation history

Reviewed Changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
source/types/commands.ts	Updates Command interface to include messages and metadata parameters
source/types/app.ts	Adds provider, model, and token counting to MessageSubmissionOptions
source/commands/export.tsx	New export command implementation with markdown formatting
source/commands/*.ts	Updates all command handlers to match new interface signature
source/commands.ts	Updates CommandRegistry execute method to pass messages and metadata
source/app/utils/appUtils.ts	Calculates total tokens and passes metadata to command execution
source/app/hooks/useAppInitialization.tsx	Registers the new export command
source/app.tsx	Passes provider, model, and token counting function to message submission
package.json	Updates ink dependency version
README.md	Documents the new export command

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[Copilot]

[nitpick] The filename generation uses a magic string replacement pattern. Consider extracting this to a helper function or using a more robust date formatting approach for better maintainability.

[Copilot]

Using map().join('') creates intermediate arrays. For better performance with large message arrays, consider using a single loop or reduce operation to build the content string directly.

Suggested change

	const markdownContent = messages.map(formatMessageContent).join('');
	const markdownContent = messages.reduce((acc, msg) => acc + formatMessageContent(msg), '');