Fix ES for for non-default branches

Closes #1349

See merge request !999

[ci skip]

[ci skip]

CE upstream

See merge request !996

Fix 500 error while navigating to the `pages_domains` 'show' page.

Closes #1447 and #1448

See merge request !993

Post username as property, not user_name

See merge request !8261

Fix state_event parameter to reopen an issue

Closes #25958

See merge request !8246

==================
= Implementation =
==================

1. The path of the page is of the form 'group/project/pages/domains/<domain_name>'
2. Rails looks at `params[:id]` (which should be the domain name), and finds the
   relevant model record.
3. Given a domain like `foo.bar`, Rails sets `params[:id]` to `foo` (should be
   `foo.bar`), and sets `params[:format]` to `bar`
4. This commit fixes the issue by adding a route constraint, so that
   `params[:id]` is set to the entire `foo.bar` domain name.

=========
= Tests =
=========

1. Add controller specs for the `PagesDomainController`. These are
   slightly orthogonal to this bug fix (they don't fail when this bug is
   present), but should be present nonetheless.
2. Add routing specs that catch this bug (by asserting that the `id`
   param is passed as expected when it contains a domain name).
3. Modify the 'RESTful project resources' routing spec shared example to
   accomodate controllers where the controller path (such as
   `pages/domains`) is different from the controller name (such as
   `pages_domains`).

Add more images to issue creation from unresolved discussions

See merge request !8279

Fixed typo in test-and-deploy-ruby-application-to-heroku.md

See merge request !8236

[ci skip]

Change earlier to task_status_short to avoid titlebar line wraps

Closes #25941

See merge request !8275

Stops GFM special characters interfering with markdown tags

See merge request !8265

Add Gitaly to the architecture of the application

See merge request !8264

Slack docs [ci skip]

See merge request !8269

Resolve "Labels are not consistent on all pages"

Closes #25951

See merge request !8256

[ci skip]

Increase left padding of filter row labels

See merge request !8258

[ci skip]

[ci skip]

[ci skip]

Fix viewing "build failed" TODOs

Closes #25979

See merge request !8262

Docs on MM auto config

See merge request !8230

Fix format of Slack when result is nil

Closes #25954

See merge request !8248

Fix hover pipeline

See merge request !8253

Fix dropdown content non appearing in MR view

Closes #25961

See merge request !8255

CE upstream

See merge request !991