chore: replace legacy repo state docs with project memory

.memory/project.md

@@ -0,0 +1,30 @@
+# Project memory
+
+- Repo: `netupgrade`
+- Language: Bash
+- Entry point: `bin/netupgrade`
+- Purpose: interactive SSH-based maintenance/upgrade CLI
+
+## Rules
+- Keep it lightweight and shell-based
+- Preserve backward compatibility when possible
+- Treat config files as trusted shell input
+- Be careful with SSH quoting and remote command construction
+- Prefer small, reviewable changes
+- Keep docs aligned with runtime behavior
+- Avoid introducing `set -euo pipefail` without validating failure semantics
+
+## Current behavior
+- Loads configs from `~/.config/netupgrade/*.cfg`
+- Uses `NODES` entries: `host;display-name;action1;action2;...`
+- Runs selected actions sequentially over SSH
+- Defaults to `root@host`, or `SSH_USER@host`
+- Logs to `~/netupgrade.log`
+- Opens the log with `$EDITOR`, then `nano`, `vi`, or `less`
+
+## Sensitive areas
+- SSH quoting
+- `cmd:<...>` execution
+- `docker-stacks:<...>` handling
+- package-manager cleanup behavior
+- error propagation