Add Calibre import workflow with Unraid setup, OPDS, and KOReader guide

Agent skill doc covering the full Calibre library workflow: importing
books via Unraid Docker containers, metadata management, tag rules,
KOReader OPDS access on Boox, and external serving options.

VAULT_MAP.md

@@ -21,6 +21,7 @@ home.md              — Personal dashboard (Obsidian Tasks widget)
 VAULT_MAP.md         — This file. Vault guide for humans and LLMs.
 README.md            — Git repo description.
 
+agent_skills/        — Runbooks and workflows for LLM/agent tasks (see below)
 copilot/             — Obsidian Copilot plugin data. Do not modify.
 Readwise/            — Readwise sync plugin data. Do not modify.
 templates/           — Note templates for journals, book notes, etc.
@@ -39,6 +40,14 @@ If you are an LLM or agent adding content to this vault, follow the guide for th
 
 The entire vault (not just `documents/`) is indexed by the notesearch skill (LlamaIndex + Ollama vector search).
 
+### Agent Skills (`agent_skills/`)
+
+Step-by-step runbooks for LLM/agent tasks. If you are an agent about to perform a task, check this folder first — there may already be a workflow written for it.
+
+- Files are freeform markdown with CLI commands, rules, and tips
+- One file per workflow (e.g., `calibre_import_workflow.md`)
+- These are living documents — update them when the process changes
+
 ### Journals (`journals/`)
 
 - One file per day, named `YYYY-MM-DD.md`