Replace workspaces with nested collections

CHANGELOG.md

@@ -7,6 +7,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- **Breaking:** workspaces are replaced by collections, optional folders that nest. A document lives at the root or in one collection, and its slug is global
+- **Breaking:** document URLs move to `/docs/<slug>` in the browser and `/api/docs/<slug>` in the API; collections live at `/collections` and `/api/collections`
+- **Breaking:** the skill scripts drop `--workspace`; `publish-document.mjs` gains `--collection <slug>` and `--root`, and the publish body accepts an optional `collectionSlug`
+- The database migrates to schema 10: documents from the `default` workspace move to the root, every other workspace becomes a root collection, and the migration refuses to run if a document slug exists in more than one workspace
+
 ## [0.0.2] - 2026-08-02
 
 ### Added

README.md

@@ -51,13 +51,17 @@ mkdir -p ~/.claude/skills/pena
 cp -R resources/skills/pena/. ~/.claude/skills/pena/
 ```
 
-verify: in a new Claude Code session, ask it to *"publish this plan to Pena"* — it should respond with a `http://127.0.0.1:5173/workspaces/...` URL.
+verify: in a new Claude Code session, ask it to *"publish this plan to Pena"* — it should respond with a `http://127.0.0.1:5173/docs/...` URL.
+
+If you upgraded Pena from a version that had workspaces, reinstall the
+skill with the same commands: its script flags and URLs changed.
 
 # How To Use
 
 1. Ask Claude Code to publish a document to Pena. It uploads referenced local
    PNG, JPEG, WebP, and GIF images, chooses an explicit title, then publishes
-   the title and staged Markdown under a workspace and stable document slug.
+   the title and staged Markdown under a stable document slug, at the root
+   or inside a collection you name.
 2. Open the URL it gives you, select any text, and leave comments. Documents can also carry interactive decision blocks — single-choice questions you answer inline.
 3. Submit the feedback. The active Claude Code session picks it up
    automatically, applies the comments, and republishes to the same slug.
@@ -67,7 +71,8 @@ The monitor stops when that Claude Code session ends. When the Monitor tool is
 not available, Pena keeps the feedback and you can still ask Claude to fetch it
 manually.
 
-Documents live in workspaces. Each immutable version contains its explicit
+Documents live at the root or inside collections, which nest like folders.
+Each immutable version contains its explicit
 title and Markdown content, with feedback attached to that exact version.
 Changing only the title still creates a version. The document view separates
 operational metadata from the reviewed body and renders the explicit title once