added mermaid and a lot of cmap changes

static/cmap/README.md

@@ -15,11 +15,19 @@ submap concepts. Automatic sizing remains active while text is edited and is
 disabled when the user resizes a concept manually.
 
 Selected concepts expose an edit handle. The host opens a modal editor for
-their independent display label, synopsis, background colour, typography and
-optional image. Page concepts retain their linked `pageSlug`; double-click is
+their shared name, aspects, people, description page, synopsis, image, external
+web address and linked wiki/CMap target, plus placement-specific background
+colour and typography. The editor has one compact tab for content, links and
+images, and a second tab for detailed colours, typography and submap
+presentation. Detailed settings can be saved as named, wiki-wide database
+styles; selected styles are applied immediately and non-default styles can be
+deleted. Its action bar remains visible while a tab scrolls.
+Structural kinds such as a sub-CMap head remain placement roles. Page concepts retain their linked `pageSlug`; double-click is
 reserved for opening that wiki page. Concepts may alternatively retain a
 `cmapSlug` for another stored CMap or a `parentCmapLink` for navigation back
-from a child map. Images are data URLs inside the persisted CMap JSON document.
+from a child map. An optional `externalUrl` accepts only HTTP(S), opens in a new
+browser tab and is shared by every placement of that concept. Images are data
+URLs inside the persisted CMap JSON document.
 Font families are selected from a practical list and font sizes are stored in
 typographic points. The host can change the linked page or CMap independently
 of the visible label and provides background and text-colour pickers.
@@ -39,6 +47,30 @@ selected inline sub-CMap or moves selected child items one level outward.
 formatting, positions, connectors, recursive submap membership and promoted
 map references. The wiki host persists this JSON document through its CMap API.
 
+## JSON interchange
+
+`/js/cmap-interchange.js` implements the versioned `racket-wiki-cmap-bundle`
+format. A bundle mirrors the normalized database model: `cmaps[]` contains the
+complete placement and presentation document, `concepts[]` contains shared
+content once per UUID, and `pages[]` contains the current Markdown, tags and
+referenced attachments of linked wiki and explanation pages. Attachments retain
+their MIME type and binary base64 content; import uploads them under the target
+page and rewrites the Markdown to the newly allocated URL. The root CMap and every included CMap retain
+their stable slug. Derived CMaps automatically include their source CMap.
+
+Presentation includes coordinates, dimensions, colours, font settings,
+sub-CMap membership, linking phrases and connectors. Connector endpoints use
+local item ids; concept identity never depends on those local ids. The formal
+contract is
+[`racket-wiki-cmap-bundle-v1.schema.json`](../schemas/racket-wiki-cmap-bundle-v1.schema.json).
+
+An external generator may use a temporary id such as `new:security-review` for
+a new concept. Every concept must also occur in at least one non-phrase
+`document.items[]` placement with coordinates. On import the server turns such
+a temporary identity into a UUID through the central Racket UUID helper. UUIDs
+already present in an export remain unchanged. Imported CMap slugs likewise
+remain unchanged.
+
 The editor keeps up to one hundred complete document states for Undo and Redo.
 One drag or resize gesture forms one history step. The public `undo`, `redo`,
 `canUndo`, `canRedo` and `resetHistory` methods are also used by the wiki host