feat(yasgui): add a "How MatGUI works" quick start tour

Five pages with three items each, a small illustration and a short
explanation. Opens on the first visit (remembered in local storage),
stays available from the help menu and the Ctrl+K search, and links to
the user guide. Embedders can set showQuickStart: false, or
quickStartOnFirstVisit: false to only offer it in the help menu.

Author: MathiasVDA

.changeset/quick-start-tour.md

@@ -0,0 +1,5 @@
+---
+"@matdata/yasgui": minor
+---
+
+"How MatGUI works": a quick start tour of five pages, each with three things to know and a small illustration, opens the first time someone uses MatGUI and stays available from the help menu and the Ctrl+K search. It links to the full user guide. Embedders can leave it out with `showQuickStart: false`, or keep it in the help menu only with `quickStartOnFirstVisit: false`.

docs/developer-guide.md

@@ -701,6 +701,13 @@ interface Config {
   // Search for saved queries, commands and settings in the top bar, also opened with Ctrl+K / Cmd+K
   showCommandPalette?: boolean;  // default: true
 
+  // "How MatGUI works" quick start tour in the help menu of the top bar
+  showQuickStart?: boolean;  // default: true
+
+  // Open the quick start tour on the first visit in a browser (remembered in local storage under
+  // "matgui_quickStart_seen"). Set to false to only offer it in the help menu
+  quickStartOnFirstVisit?: boolean;  // default: true
+
   // Layout orientation: 'vertical' or 'horizontal'
   orientation?: 'vertical' | 'horizontal';  // default: 'vertical'
 

docs/user-guide.md

@@ -14,6 +14,7 @@
   - [Common SPARQL Query Types](#common-sparql-query-types)
 - [Getting Started](#getting-started)
   - [Accessing MatGUI](#accessing-matgui)
+  - [Quick Start Tour](#quick-start-tour)
   - [Running Matgui with Docker](#running-matgui-with-docker)
   - [Your First Query](#your-first-query)
   - [Saving Your Work](#saving-your-work)
@@ -149,6 +150,20 @@ This excellent resource covers:
 
 Matgui is available at: **[https://matgui.matdata.eu/](https://matgui.matdata.eu/)**
 
+### Quick Start Tour
+
+The first time you open MatGUI in a browser, **How MatGUI works** shows you around in five short pages, with three things to know on each:
+
+1. **Write and run a query**: pick an endpoint, write with autocomplete, run with `Ctrl+Enter`
+2. **Explore the results**: switch views, describe a resource, download the results
+3. **Keep your queries**: work in tabs, save to a workspace, share a link
+4. **Let MatGUI help**: insert snippets, look at the endpoint, ask the AI assistant (or hover an IRI, when the site has no AI assistant)
+5. **Find your way**: search everything with `Ctrl+K`, open the side panel with `Ctrl+B`, switch the theme and open the settings
+
+Click **Next** and **Back**, the dots at the bottom, or use the `←` and `→` keys to move between the pages. **Read the full user guide** opens this guide. Close the tour with **Skip**, **Start querying** on the last page, the × or `Esc`. MatGUI remembers in your browser that you saw it and doesn't open it again by itself.
+
+To see it again, click **Help** (?) in the top bar and pick **How MatGUI works**, or search for it with `Ctrl+K`. Sites that embed MatGUI can leave the tour out, or keep it in the help menu without opening it on the first visit.
+
 ### Running Matgui with Docker
 
 You can run Matgui locally using Docker, which is especially useful when working with local SPARQL endpoints.
@@ -352,7 +367,7 @@ From left to right:
 - **MatGUI**: the name of the application (sites that embed MatGUI can hide it)
 - **Query tabs**: one tab per query. The active tab is raised. Tabs that hold a saved (managed) query show a small dot before their name; the dot turns amber when the query has unsaved changes. Hover a tab to show its close button (×), click **+** to add a tab
 - **Search queries and commands** (`Ctrl+K`, or `⌘K` on a Mac): see [Search](#search)
-- **Help** (?): opens the MatGUI user guide in a new browser tab
+- **Help** (?): opens a menu with **How MatGUI works** (the [quick start tour](#quick-start-tour)) and **Documentation**, the MatGUI user guide in a new browser tab
 - **Theme** (sun / moon): switches between the light and dark theme
 - **Settings** (gear): opens the settings of the active tab
 
@@ -362,7 +377,7 @@ Click **Search queries and commands** in the top bar, or press `Ctrl+K` (`⌘K`
 
 - **Queries**: the saved queries of all your workspaces, with the workspace and folder they are in. Pick one to open it in a new tab, or to go to the tab that already has it open
 - **Snippets**: the code snippets of the [Insert menu](#insert-menu), found by name, group or the code they write (`filter` finds the comparison snippets). Pick one to insert it at the cursor
-- **Commands**: Run query, New tab, Insert snippet, Insert PREFIX declarations, Switch endpoint, Explore endpoint, Show saved queries, Toggle side panel, Toggle side-by-side layout, Format, Share, Save, Download, full screen editor, dark mode and the documentation. Commands with a shortcut show it at the right
+- **Commands**: Run query, New tab, Insert snippet, Insert PREFIX declarations, Switch endpoint, Explore endpoint, Show saved queries, Toggle side panel, Toggle side-by-side layout, Format, Share, Save, Download, full screen editor, dark mode, How MatGUI works and the documentation. Commands with a shortcut show it at the right
 - **Settings**: every page of the settings (General, SPARQL endpoints, Workspaces, Prefixes, Editor, AI, Import / export, Keyboard shortcuts, About), for example type `prefixes` and pick **Settings: Prefixes**
 
 Type `>` first to search commands and settings only. Snippets and settings show up once you type something. Use `↑` and `↓` to move, `Enter` to open and `Esc` to close.

packages/yasgui/src/CommandPalette.ts

@@ -386,6 +386,18 @@ export default class CommandPalette {
         },
       });
     }
+    if (yasgui.quickStart) {
+      const quickStart = yasgui.quickStart;
+      commands.push({
+        section: "commands",
+        label: "How MatGUI works",
+        icon: "compass",
+        keywords: "help quick start tour introduction onboarding",
+        run: () => {
+          quickStart.open();
+        },
+      });
+    }
     if (yasgui.config.helpUrl) {
       const helpUrl = yasgui.config.helpUrl;
       commands.push({