chore: move to Eslint flat config

Make the big move to Eslint flat config format. The outcome of Eslint
still should be the same, but some things has changed:
- `eslint-plugin-github` is dropped, flat configs have been out for a
while and most eslint plugins support it, but for no reason and no
activity in sight this plugin is likely not going to support flat config
for a while and to avoid other plugins not being able to update (as they
are requiring flat configs) drop the github rules.
- Nested configs don't work properly and are unified into the root
eslint config, this unification did cause some conflicts and thats why
the `import-x` is in a seperate 'group' to exclude targeting Vue files.
- The `eslint-plugin-i` is deprecated and `esplint-plugin-import-x` is
its succesor which has better support for flat configs, the same rules
are still applied.

The majority of the flat config was generated by
`@eslint/migrate-config` tool.

web_src/js/components/.eslintrc.yaml

@@ -1,21 +0,0 @@
-plugins:
-  - eslint-plugin-vue
-  - eslint-plugin-vue-scoped-css
-
-extends:
-  - ../../../.eslintrc.yaml
-  - plugin:vue/vue3-recommended
-  - plugin:vue-scoped-css/vue3-recommended
-
-parserOptions:
-  sourceType: module
-  ecmaVersion: latest
-
-env:
-  browser: true
-
-rules:
-  vue/attributes-order: [0]
-  vue/html-closing-bracket-spacing: [2, {startTag: never, endTag: never, selfClosingTag: never}]
-  vue/max-attributes-per-line: [0]
-  vue-scoped-css/enforce-style-type: [0]