Remove sync-roots workaround when Claude Code fixes /add-dir root notifications

[m-wells]

Context

Claude Code's /add-dir command does not send notifications/roots/list_changed to MCP servers. This means Catenary never learns about directories added mid-session, and path-validated tools like list_directory reject paths in the new directory.

Upstream issue: anthropics/claude-code#26663

Current Workaround

A PreToolUse hook runs catenary sync-roots on every tool call. It:

1. Parses the Claude Code transcript JSONL for /add-dir confirmation messages
2. Sends discovered roots to the running session's notify socket
3. Uses a byte-offset cache to avoid re-scanning the full transcript

Files involved:

• src/main.rs — SyncRoots subcommand and run_sync_roots()
• src/notify.rs — AddRoots variant in NotifyRequest, process_add_roots()
• src/bridge/path_security.rs — roots() getter on PathValidator
• plugins/catenary/hooks/hooks.json — PreToolUse hook entry

When to close

When Claude Code sends notifications/roots/list_changed after /add-dir, the sync-roots hook becomes unnecessary. At that point:

1. Remove the SyncRoots subcommand from src/main.rs
2. Remove the AddRoots variant from NotifyRequest in src/notify.rs (keep process_add_roots on the server side — it's useful for any root addition path)
3. Remove the PreToolUse hook from plugins/catenary/hooks/hooks.json
4. The roots() getter on PathValidator can stay — it's generally useful