fix: make sidebar sticky, fix styles, responsiveness, scroll and remove padding

[rpenido]

Description

This PR fixes an issue introduced by #3056 and #3055, in which the sidebar lost its sticky style after adding a div to wrap it, alongside some styles, responsiveness, and scroll.

It also removes the padding added by #3055, which causes misalignment with the main content on the left.

Supporting information

• Related to fix: course unit sidebar slot #3055 (comment)

Testing instructions

• Checkout this PR and run npm run build
• Check with the following env.config.jsx to see the behaviour with insert/wrapping components:

import { PLUGIN_OPERATIONS, DIRECT_PLUGIN } from '@openedx/frontend-plugin-framework';

import { Card } from "@openedx/paragon"

const config = {
  pluginSlots: {
    'org.openedx.frontend.authoring.course_unit_sidebar.v2': {
      keepDefault: true,
      plugins: [
        {
          op: PLUGIN_OPERATIONS.Insert,
          widget: {
              id: 'course-unit-sidebar',
              priority: 1,
              type: DIRECT_PLUGIN,
              RenderWidget: () => <Card><Card.Header title="v2"/></Card>,
          },
        },
        {
            op: PLUGIN_OPERATIONS.Wrap,
            widgetId: 'default_contents',
            wrapper: ({component}) => (
                <div className="flex-fill d-flex overflow-hidden" style={{ border: 'thick dashed green' }}>
                    {component}
                </div>
            ),
        },
      ],
    },
    'org.openedx.frontend.authoring.course_outline_sidebar.v1': {
      keepDefault: true,
      plugins: [
        {
          op: PLUGIN_OPERATIONS.Insert,
          widget: {
              id: 'course-sidebar',
              priority: 1,
              type: DIRECT_PLUGIN,
              RenderWidget: () => <Card><Card.Header title="v2"/></Card>,
          },
        },
        {
            op: PLUGIN_OPERATIONS.Wrap,
            widgetId: 'default_contents',
            wrapper: ({component}) => (
                <div className="flex-fill d-flex overflow-hidden" style={{ border: 'thick dashed green' }}>
                    {component}
                </div>
            ),
        },
      ],
    },
  },
};

export default config;

Note: The flex classes in the wrapping divs are necessary so the content adapts to the remaining space correctly.

• Check that the sidebar on both Course Outline and Unit Outline has 100vh and occupies the whole left while scrolling.
• Resize your browser vertically and check if a scrollbar is shown inside the sidebar, and you can see the whole content.

Best Practices Checklist

We're trying to move away from some deprecated patterns in this codebase. Please
check if your PR meets these recommendations before asking for a review:

• Any new files are using TypeScript (.ts, .tsx).
• Avoid propTypes and defaultProps in any new or modified code.
• Tests should use the helpers in src/testUtils.tsx (specifically initializeMocks)
• Do not add new fields to the Redux state/store. Use React Context to share state among multiple components.
• Use React Query to load data from REST APIs. See any apiHooks.ts in this repo for examples.
• All new i18n messages in messages.ts files have a description for translators to use.
• Avoid using ../ in import paths. To import from parent folders, use @src, e.g. import { initializeMocks } from '@src/testUtils'; instead of from '../../../../testUtils'

[openedx-webhooks]

Thanks for the pull request, @rpenido!

This repository is currently maintained by @bradenmacdonald.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.52%. Comparing base (adf92ef) to head (e7b8ce6).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3057   +/-   ##
=======================================
  Coverage   95.52%   95.52%           
=======================================
  Files        1393     1393           
  Lines       32969    32971    +2     
  Branches     7592     7600    +8     
=======================================
+ Hits        31493    31495    +2     
  Misses       1408     1408           
  Partials       68       68           

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