Feat: Add context collection list management functions

[tninja]

No description provided.

[Copilot]

Pull Request Overview

This PR adds context collection list management functions to the AI code interface, enabling users to capture and maintain repository-specific context information that gets included in AI prompts.

• Introduces functions to add, list, and clear context entries per Git repository
• Integrates stored context information into existing AI prompt generation functions
• Adds a new transient menu command "@" for managing context

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
ai-code-interface.el	Adds new "@" menu item for context management action
ai-code-file.el	Implements core context management functions including storage, display, clearing, and formatting of repository context
ai-code-discussion.el	Integrates repository context into question and exception investigation prompts
ai-code-change.el	Integrates repository context into code change prompts

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[tninja]

@copilot open a new pull request to apply changes based on the comments in this thread

[Copilot]

@tninja I've opened a new pull request, #51, to work on those changes. Once the pull request is ready, I'll request review from you.