pikuri-workspace

pikuri-workspace adds "operate on a directory tree" to pikuri-core agents: the +Pikuri::Tool::Workspace+ seam (abstract base + +Workspace::Cwd+) that scopes filesystem access to a chosen root, the +Pikuri::Tool::Confirmer+ seam (+AUTO_APPROVE+ + +TERMINAL+) for user-state mutations, and five tools wired to those seams: +Pikuri::Tool::Read+, +Pikuri::Tool::Write+, +Pikuri::Tool::Edit+, +Pikuri::Tool::Grep+, and +Pikuri::Tool::Glob+. Self-contained — no shell execution; +Pikuri::Tool::Bash+ ships in pikuri-code on top of these.