viewer: migrate to vue 3, general refactoring and cleanup

Non-exhaustive list of fixes and improvements done at the same time:

- html default background to grey (avoids white flash during init)
- unified links behavior
- added more theme variables
- removed the flex-expand transition (it wasn't working) and replaced it
  with a slide
- fixed LdLoading not centered on the content
- title on removable tags
- fixed an issue with encoded URI from vue-router
- unified Item resource URLs
- removed the iframe for PlainTextViewer (it wasn't working properly)
  and replaced it with a pre
- fixed clear and search buttons tabindex
- fixed the information panel bumping up during the fade animation of
  tag's dropdown
- fixed some focus outlines not appearing correctly
- moved CSS variables to the :root context
- Code cleaning

GitHub: closes #217
GitHub: closes #300
GitHub: closes #297
GitHub: closes #105
GitHub: closes #267
GitHub: closes #275
GitHub: closes #228
GitHub: closes #215
GitHub: closes #112

1 files changed, 3 insertions, 1 deletions

diff --git a/viewer/.gitignore b/viewer/.gitignore
index f1ab425..dd02288 100644
--- a/viewer/.gitignore
+++ b/viewer/.gitignore
@@ -2,6 +2,7 @@
 node_modules
 /dist
 
+
 # local env files
 .env.local
 .env.*.local
@@ -10,10 +11,11 @@ node_modules
 npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
+pnpm-debug.log*
 
 # Editor directories and files
 .idea
-.vscode/settings.json
+.vscode
 *.suo
 *.ntvs*
 *.njsproj