SKALE-4527 Base library structure, schains internal contract, tests

Author: dmytrotkk

.env-sample

@@ -0,0 +1 @@
+ENDPOINT=

.env_example

@@ -1,10 +1,51 @@
-.idea/
-.vscode/
-node_modules/
-build
+lib-cov
+*.seed
+*.log
+*.csv
+*.dat
+*.out
+*.pid
+*.gz
+*.swp
+
+pids
+logs
+results
+tmp
+
+# Build
+public/css/main.css
+
+# Coverage reports
+coverage
+
+# API keys and secrets
 .env
+
+# Dependency directory
+node_modules
+bower_components
+
+# Editors
+.idea
+*.iml
+
+# OS metadata
 .DS_Store
-*.tgz
-npm-debug.log*
-/.changelog
-.eslintcache
+Thumbs.db
+
+# Ignore built ts files
+dist/**/*
+
+# ignore yarn.lock
+yarn.lock
+
+### custom
+
+abis
+
+build/
+data/
+
+.env-sdk
+manager.json