Merged PR 162: Implement symbols and other stuff (see desc)

Implement symbols
- Add, Remove, Select Container
- Form
- Link with container
- Symbol behavior application to container (move to x with xpositionreference)

Important changes
- Remove SelectedContainer from HistoryState, meaning that it will be slower for each load but will be faster for each operations* (SetHistory, SelectContainer, DeleteContainer, SymbolOperations)
- ElementsSidebar now opens with isSidebarOpen meaning that both sidebar will open on toggle
- Moved camelize, transformX, restoreX to different modules (stringtools.ts, svg.ts)

azure-pipelines.yml

@@ -21,7 +21,7 @@ steps:
     path: $(pnpm_config_cache)
   displayName: Cache pnpm
 
-- script: |
+- bash: |
     curl -f https://get.pnpm.io/v6.16.js | node - add --global pnpm@7
     pnpm config set store-dir $(pnpm_config_cache)
   displayName: "Setup pnpm"
@@ -31,7 +31,8 @@ steps:
     versionSpec: '16.x'
   displayName: 'Install Node.js 16.x LTS'
 
-- script: |
+- bash: |
+    set -euo pipefail
     node --version
     node ./test-server/node-http.js &
     jobs
@@ -46,7 +47,8 @@ steps:
     versionSpec: '>=18.7.0'
   displayName: 'Install Node.js Latest'
 
-- script: |
+- bash: |
+    set -euo pipefail
     node --version
     node ./test-server/node-http.js &
     jobs