Memory Center: review gates for what the agent remembers

Memory Center keeps saved context, pending proposals, Dream state, and side-chat review visible before anything becomes permanent.

Memory should not be a silent side effect. MendCode treats generated memory as a proposal first, keeps project and global scopes separate, and lets the user inspect why a change exists before applying it.

Dream is the maintenance layer around that model. It can consolidate evidence and suggest cleanup, but the visible state remains reviewable from the TUI instead of becoming invisible background mutation.

The side chat is intentionally scoped to memory work: explain categories, inspect pending proposals, draft actions, and keep the main coding agent from becoming the only way to understand context.