Change some establish_connection logic

Move new default initializers into separate directory

[ci skip]Fix wrong require path raising LoadError

ActionController::Parameters: Fix #dig doc code

This example code wasn't getting wrapped in a `<code>` tag due to incorrect indentation.

rename enum_prefix and enum_suffix options to _prefix and _suffix [ci skip]

`:enum_prefix` and `:enum_suffix` was changed to `:_prefix` and `:_suffix`
in #20999.

- These initializers are new defaults for Rails 5 and newly generated
  apps do not need to change them.
- Fixes #25181

Follow up to e45f388e.

When changing the generated integration tests to assert redirects with
an absolute path this redirection check in `assert_redirected_to` against
the absolute response location would now pass:
https://github.com/rails/rails/blob/af245aaf3a1c447752a1b5895adddc66e5f73c00/actionpack/lib/action_dispatch/testing/assertions/response.rb#L55

Thus we'd break early instead of hitting `assert_operator` and have
2 fewer assertions per `assert_redirected_to` as `assert_operator`
is composed of 2 assertions internally:
https://github.com/seattlerb/minitest/blob/4e146b1515b19a5c474e39c174b037510f6dbc6e/lib/minitest/assertions.rb#L254-L258

Deduct 2 assertions for 2 redirects taking the expected count down by 4
in total for the two failing tests.

Remove public/ files for API apps

The first comment does not explain anything that the code doesnt and the second is now irrelevant with the dedicated API mode

- Fixes #25180

fix incorrect class name [ci skip]

Use `add_index` instead of `execute` in guides [ci skip]

[ci skip] Reword doc for around_enqueue callback

Taken literally, the documentation suggests that the callback gets
called twice (before and after enqueueing). By wording it similarly to
that of around_perform this confusion is avoided.

cometic updates to security guide - fixes #25058 [ci skip]

Remove unused `association_for_table` private method

[ci skip] Fix ActionCable Guides

add missing `as` to request kwargs of `ActionDispatch::IntegrationTest`

Add test for `delegate_missing_to` where method doesn't exist

Follow up to #21671

Default worker pool size was changed from 100 to 4 at #24376

`association_for_table` is unused since 50a8cdf0.

Bash markdown syntax

Added 'sh' for markdown formatting as bash.

Fix `has_one` `enum` `where` queries

Fixes #25128

Docs: Clarify when assoc. methods persist [ci skip]

Because I can never remember if `collection_singular_ids=` persists
or not (it does).

[ci skip]

Revert back to a compatible bundler version