Promote installation to navbar, clarify install path

Move /learn/00-installation to /install and add it as the first navbar
item. Lead with pak::pak from GitHub since blockr is under heavy
development; mention CRAN as fallback. Spell out that blockr is a
meta-package that bundles core/dock/dag/dplyr/ggplot/io, and recommend
blockr.session and blockr.bi for real applications. Point to the package
overview as the source of truth for everything else.

Author: christophsax

.vitepress/config.js

@@ -13,6 +13,7 @@ module.exports = {
     logo: { light: '/logos/logo-e4-light.svg', dark: '/logos/logo-e4-dark.svg' },
     siteTitle: 'blockr',
     nav: [
+      { text: 'Install', link: '/install' },
       { text: 'Learn', link: '/learn/01-build-your-first-app' },
       { text: 'Docs', link: '/docs/concepts/01-reactivity' },
       { text: 'Videos', link: '/videos/getting-started' },
@@ -28,7 +29,6 @@ module.exports = {
       '/learn/': [{
         text: 'Learn',
         items: [
-          { text: 'Installation', link: '/learn/00-installation' },
           { text: 'Build your first app', link: '/learn/01-build-your-first-app' },
           { text: 'Build a dashboard', link: '/learn/02-build-a-dashboard' },
           { text: 'Create a custom block', link: '/learn/03-create-a-block' }

install.md

@@ -0,0 +1,55 @@
+---
+title: Install blockr
+description: Install the blockr meta-package and optional extras.
+---
+
+# Install blockr
+
+You need [R](https://www.r-project.org/) 4.1 or later. Most users access blockr through a hosted server (e.g. [blockr.cloud](https://blockr.cloud)) and don't need to install anything locally.
+
+## blockr <Badge type="tip" text="recommended" />
+
+blockr is on CRAN, but it's under heavy active development. Install from GitHub to get current bug fixes and features:
+
+```r
+# install.packages("pak")
+pak::pak("BristolMyersSquibb/blockr")
+```
+
+[blockr](https://bristolmyerssquibb.github.io/blockr/) is a meta-package. It pulls in the core engine and the main block libraries: [blockr.core](https://bristolmyerssquibb.github.io/blockr.core/), [blockr.dock](https://bristolmyerssquibb.github.io/blockr.dock/), [blockr.dag](https://bristolmyerssquibb.github.io/blockr.dag/), [blockr.dplyr](https://bristolmyerssquibb.github.io/blockr.dplyr/), [blockr.ggplot](https://bristolmyerssquibb.github.io/blockr.ggplot/), [blockr.io](https://bristolmyerssquibb.github.io/blockr.io/).
+
+Launch a board:
+
+```r
+blockr::run_app()
+```
+
+If you'd rather use the released version:
+
+```r
+install.packages("blockr")
+```
+
+## Optional extras
+
+These packages aren't bundled into the meta-package. Install whichever you need.
+
+### Session management: [blockr.session](https://bristolmyerssquibb.github.io/blockr.session/)
+
+Save, restore, and share board state across users.
+
+```r
+pak::pak("BristolMyersSquibb/blockr.session")
+```
+
+### Dashboard blocks: [blockr.bi](https://github.com/cynkra/blockr.bi)
+
+Drilldown, crossfilter, tiles, and KPI cards. New, but you'll want these for complex dashboards.
+
+```r
+pak::pak("cynkra/blockr.bi")
+```
+
+## More
+
+Other packages (AI assistant, code export, stats, vertical demos) live in the [package overview](/packages/). The list there is the source of truth and may shift as packages stabilise or get folded into the meta-package.

learn/00-installation.md

@@ -3,7 +3,7 @@
 This tutorial will get you started with blockr in just a few minutes.
 By the end, you will have built your first data pipeline.
 
-Make sure blockr is running — see [Installation](00-installation) if you haven't set it up yet.
+Make sure blockr is running. See [Installation](/install) if you haven't set it up yet.
 
 ## Load data