feat(file-upload): added dropzone area (#DS-2356)

[NikGurev]

Full-screen Dropzone

1. Open https://koobiq-next--prs-1299-egvz9il5.web.app/ru/components/file-upload/examples#%D0%B4%D1%80%D0%BE%D0%BF-%D0%B7%D0%BE%D0%BD%D0%B0
2. Click and hold a file in the system file manager and drag it over the browser window opened in step 1

Result: the full-screen dropzone should appear

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Local Dropzone

1. Open https://koobiq-next--prs-1299-egvz9il5.web.app/ru/components/file-upload/examples#%D0%B4%D1%80%D0%BE%D0%BF-%D0%B7%D0%BE%D0%BD%D0%B0
2. Set the toggle labeled “full screen” to unchecked
3. Click and hold a file in the system file manager and drag it over the area with the header “Local dropzone”

Result: the local dropzone should appear

Press for description in ru-RU

Full-screen Dropzone

1. Открыть https://koobiq-next--prs-1299-egvz9il5.web.app/ru/components/file-upload/examples#%D0%B4%D1%80%D0%BE%D0%BF-%D0%B7%D0%BE%D0%BD%D0%B0
2. "Зажать" файл в менеджере файлов системы и навести на окно браузера с открытой на 1 шаге вкладкой

Результат: должна открыться full-screen dropzone

Local dropzone

1. Открыть https://koobiq-next--prs-1299-egvz9il5.web.app/ru/components/file-upload/examples#%D0%B4%D1%80%D0%BE%D0%BF-%D0%B7%D0%BE%D0%BD%D0%B0
2. Toggle с лейблом "full screen" сделать unchecked
3. "Зажать" файл в менеджере файлов системы и навести на область с хедером "Local dropzone"

Результат: должна открыться local dropzone

[github-actions]

Visit the preview URL for this PR (updated for commit 93c5630):

https://koobiq-next--prs-1299-egvz9il5.web.app

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[github-actions]

🚨 E2E tests failed

Review the report for details.

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💡 Comment /approve-snapshots to approve snapshot changes.

[github-actions]

🚨 E2E tests failed

Review the report for details.

---

💡 Comment /approve-snapshots to approve snapshot changes.

[github-actions]

🚨 E2E tests failed

Review the report for details.

---

💡 Comment /approve-snapshots to approve snapshot changes.

[github-actions]

🚨 E2E tests failed

Review the report for details.

---

💡 Comment /approve-snapshots to approve snapshot changes.

[github-actions]

🚨 E2E tests failed

Review the report for details.

---

💡 Comment /approve-snapshots to approve snapshot changes.

[NikGurev]

/approve-snapshots/approve-snapshots

[github-actions]

🔄 Updating snapshots.

[github-actions]

✅ Snapshots updated!

[rmnturov]

После дропа файла в дропзону фокус на ней должен оказываться. Дополню доку.