feat(sessions): Add automatic session cleanup and retention policy

[bl-ue]

This PR is the third in a series of PRs that implement automatic chat recording and resuming in both interactive and non-interactive modes, with command line flags for non-interactive resuming and session management, and an interactive session browser.

PR #4401 was the original monolithic PR, which implemented this feature from the ground up. It's too large to merge as-is, however, and so it was broken up into several smaller PRs, of which this PR is the third.

Please see #4401's description for the full context of this PR. The original monolithic PR's description contains a detailed analysis of the entire system, with an example of the recording JSON and a demo video.

[gemini-code-assist]

Summary of Changes

Hello @bl-ue, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces automatic session cleanup and retention policies to the CLI, enhancing the management of recorded chat sessions. It allows users to configure how long or how many sessions are kept, preventing an accumulation of old data. This is a crucial step in the ongoing development of the chat recording and resuming feature, ensuring that the system remains efficient and user-friendly by automatically managing session storage.

Highlights

• Automatic Session Cleanup Configuration: Introduced new configuration settings for automatic chat session cleanup, allowing users to define retention policies based on age or count.
• Session Cleanup Logic Implementation: Implemented the core logic for identifying and deleting expired chat sessions, ensuring the current session is always preserved and handling various error scenarios gracefully.
• Integration into CLI Startup: Integrated the session cleanup process into the CLI's startup sequence, so cleanup runs automatically when the application initializes.
• Comprehensive Testing: Added extensive unit and integration tests for the session cleanup functionality, covering various configuration scenarios, edge cases, and error handling.
• Part of Larger Feature Rollout: This PR is the third in a series of nine, contributing to the larger feature of automatic chat recording and resuming, broken down from a monolithic PR for easier review and integration.

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[gemini-code-assist]

Code Review

This pull request introduces an automatic session cleanup feature, which is a great addition for managing disk space. The implementation is well-tested and handles many edge cases gracefully. However, I've found a few critical and high-severity issues in the core cleanup logic:

1. The count-based retention (maxCount) logic is flawed and may not delete the correct number of sessions.
2. The minRetention setting is ignored, with a hardcoded 1-day minimum being used instead.
3. The logic to identify the currently active session to prevent its deletion is buggy and could fail, potentially leading to the deletion of the user's active session.
4. The method for flagging the current session in the session list is fragile and should be made more robust.

I've provided detailed comments and code suggestions to address these issues. Once these are fixed, the feature should be solid.

[bl-ue]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces a robust session cleanup mechanism based on retention policies (age and count). The implementation is well-structured, with clear separation of concerns into session utilities, cleanup logic, and configuration. The changes are accompanied by comprehensive unit and integration tests, ensuring the feature is reliable and handles edge cases gracefully. My main feedback concerns improving error handling to prevent silent failures in case of unexpected issues like file system permissions.

[bl-ue]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces a session cleanup and retention policy, which is a valuable addition for managing session files. The implementation is robust, with good test coverage for various scenarios. I've identified a potential high-severity race condition in the cleanup logic that could affect users running multiple concurrent sessions, and I've provided a suggestion to address it. Additionally, I found a critical issue where a method is called that does not appear to be defined, which would likely cause a runtime error.

[bl-ue]

@mrcabbage972 Yes, done. Thank you for the review!

[mrcabbage972]

@bl-ue can you please fix the CI issues so this PR can be merged?

[bl-ue]

@mrcabbage972 Done.

[bl-ue]

Hi @mrcabbage972, I'm not sure what the last test failure on Windows was about. It didn't appear to be related to my changes, and I couldn't reproduce it locally on Windows with npm test or npm test:ci. I just merged main and fixed the merge conflicts, which may fix the failure. Will you please approve the workflows again?