Add devc sync to copy devcontainer sessions to host

[DarkaMaul]

Summary

• Adds devc sync [project] command that copies Claude Code session logs from devcontainer volumes to ~/.claude/projects/ on the host, so /insights can analyze them
• Auto-discovers devcontainers (running + stopped) via the devcontainer.local_folder Docker label — no need to know container names or IDs
• Reads CLAUDE_CONFIG_DIR from container env vars to handle non-standard paths (e.g. .claude_data)
• Uses docker cp only, so it works on stopped containers without docker exec
• Incremental sync — only copies new/updated files, safe to run repeatedly

Usage

devc sync              # Sync sessions from all devcontainers
devc sync crypto       # Filter by project name (case-insensitive substring)

Test plan

• shellcheck install.sh passes clean
• devc sync discovers both running and stopped devcontainers
• Sessions from stopped container with non-standard CLAUDE_CONFIG_DIR are synced correctly
• Second run shows 0 files synced (incremental check works)
• Project name filter works (devc sync ziz only syncs zizmor)

🤖 Generated with Claude Code

[disconnect3d]

Wouldn't it be better to run /insights within the container and copy the resulting filepath? I'd be in favor of that instead of a sync command

The devc cp from #30 could be used to copy the insights rendered file 😅

[disconnect3d]

After re-reading this I think the idea here is to get the chat logs to get /insights from all Claude sessions globally, even those created within the container...

Is that really any important/useful? I just hope this wouldn't create any case where this could blow up/hijack host etc.

[DarkaMaul]

Yes - my idea was to have an easy way to sync one way the sessions from the container to the host, so my /insights command could also get info from what I'm doing inside devcontainers.

I'm unsure of the threat model here - we're only copying JSON files, but maybe Claude Code does something more with the files it's loading during the analysis?

[disconnect3d]

Yea I have no idea either; I bet it could lead to some prompt injection at some point, or, if the file is a symlink then maybe it can make claude read some other file from the filesystem on the host?

[disconnect3d]

Anyway: I think we can add it but we could somehow point out that it may not be safe/secure or something?