add wip docs

Author: reeganviljoen

docs/guide/caching.md

@@ -0,0 +1,42 @@
+---
+layout: default
+title: Caching
+parent: How-to guide
+---
+
+# Caching
+
+Experimental
+{: .label }
+
+Components can implement caching by marking the depndencies that a digest can be built om using the cache_on macro, like so:
+
+```ruby
+class CacheComponent < ViewComponent::Base
+  include ViewComponent::Cacheable
+
+  cache_on :foo, :bar
+  attr_reader :foo, :bar
+
+  def initialize(foo:, bar:)
+    @foo = foo
+    @bar = bar
+  end
+end
+```
+
+```erb
+<p><%= view_cache_dependencies %></p>
+
+<p><%= Time.zone.now %>"></p>
+<p><%= "#{foo} #{bar}" %></p>
+
+```
+will result in
+```html
+<p>foo-bar</p>
+
+<p>2025-03-27 16:46:10 UTC</p>
+<p> foo bar</p>
+```
+