Task: Implement shell list/add/remove commands for book

Create the book shell script set (list/get, add, remove, history, help) in projects/ores.shell/scripts/library/books/, mirroring the structure of countries and currencies, so operators can manage books from the REPL shell.

• books/ submenu registered in the REPL.
• list (get) script implemented and working against a live environment.
• add script implemented and working.
• remove script implemented and working.
• history script implemented and working.
• help script implemented.
• All commands call the service via NATS (not direct repository access).

(Implementation strategy. Written when work starts; key decisions are distilled into the parent story's * Decisions at close, but the plan itself stays — it is the historical record of what we did.)

Abandoned in favour of the "Shell entity commands — top-level commissioning story" capture (doc/agile/product_backlog/inbox/shell_commands_codegen_top_level_story.org, id 8BCD0D1C-AAFB-4FAA-A0E3-022FC6EF93C2), which explicitly supersedes per-commission shell tasks: ores.shell has no codegen profile, and shell commands should be established/templatized once as a horizontal layer (reference entity, generated aggregator, codegen facet) rather than hand-written per entity as this task would have done. No shell code was written for book.