feat(web/panettone): Add "All Issues" link on issue page

This was something that was complained about verbally - if someone gets
a link to an issue directly it's nice to be able to click on a link to
view all issues.

Change-Id: Id4e0c7208edc51980c6577bb10e6c6dea1e7ab55
Reviewed-on: https://cl.tvl.fyi/c/depot/+/1412
Tested-by: BuildkiteCI
Reviewed-by: kanepyork <rikingcoding@gmail.com>

web/panettone/src/css.lisp

@@ -144,6 +144,16 @@
       :color ,color/gray
       :font-size "1.5rem"))
 
+    (nav
+     :display :flex
+     :color ,color/gray)
+
+    (footer
+     :border-top "1px" "solid" ,color/gray
+     :padding-top "1rem"
+     :margin-top "2rem"
+     :color ,color/gray)
+
     ,@(button '.new-issue)
 
     (.alert

web/panettone/src/panettone.lisp

@@ -365,7 +365,9 @@ updated issue"
                          (who:esc (displayname author))
                          " at "
                          (who:esc (format-dottime (created-at comment)))))))))
-           (render/new-comment (get-id issue)))))))))
+           (render/new-comment (get-id issue))))))
+      (:footer
+       (:nav (:a :href "/" "All Issues"))))))
 
 (defun render/not-found (entity-type)
   (render