ActiveStorage::BaseController subclasses ActionController::Base.
ActionController::Base has an "inherited" hook set that includes the
routing helpers to any subclass of AC::Base.  Since
ActiveStorage::BaseController is a subclass of AC::Base, it will get
routing helpers included automatically.  Unfortunately, when the
framework is eagerly loaded, ActiveStorage::BaseController is loaded
*before* the applications routes are loaded which means it attempts to
include an "in flight" module so it gets an exception.

This commit allows a class that's interested in being extended with
routing helpers register itself such that when the routes are finalized,
it will get the helpers included.  If the routes are already finalized,
then the helpers get included immediately.

This commit eagerly builds the route helper module after the routes have
been drawn and finalized.  This allows us to cache the helper module but
not have to worry about people accessing the module while route
definition is "in-flight", and automatically deals with cache
invalidation as the module is regenerated anytime someone redraws the
routes.

The restriction this commit introduces is that the url helper module can
only be accessed *after* the routes are done being drawn.

Refs #24554 and #32892

This patch removes deprecated catch-all routes from AM

Remove deprecated catch-all route in the AV tests

Abandon TOP support.

Initially, `TOP` was introduced to support `limit` for MSSQL database.
Unlike PostgreSQL/MySQL/SQLite, MSSQL does not have native `LIMIT`/`OFFSET` support.
The commit adding `TOP` is 1a246f71.

However, it figured out that `TOP` implementation was weak and it's not sufficient
to also support `OFFSET`, then `TOP` was substituted with
`ROW_NUMBER()` subquery in be48ed30.
This is a well known trick in MSSQL -
https://stackoverflow.com/questions/2135418/equivalent-of-limit-and-offset-for-sql-server.

So now we don't need this `visit_Arel_Nodes_Top` at all.
It does nothing useful but also adds an extra space after `SELECT` when `LIMIT` is being
used for **any** database.

Fix rails guides markdown.rb and renderer.rb to use custom header id

Improve phrasing of one sentence in the contributing guide

It also removes a monkey patch from AM::Base

We should be able to remove this once the catch-all route is gone from
AP

This commit removes a deprecated catch-all route in the AV tests.  It
defines and includes the necessary routes for each test such that we
don't need the catch-all anymore.

This also helps push us toward #33970

Eagerly define attribute methods in production

update mini_magick to the latest version

v 4.9.2 avoids some warnings that show in our tests.

Although Gemfile.lock currently specifies 4.8.0, the CI already runs 4.9.2
so 4.8.0 warnings do not show in our CI logs.

The attribute methods for a model are currently defined lazily the first
time that model is instantiated, even when `config.eager_load` is true.
This means the first request to use each model incurs the cost, which
usually involves a database round trip to fetch the schema definition.

By defining the attribute methods for all models while the application
is booting, we move that work out of any individual request. When using
a forking web server, this also reduces the number of times the schema
definition is queried by doing it once in the parent process instead of
from each forked process during their first request.

Similar to Action View's and Action Controller's instrument helpers.

Encode Content-Disposition filenames on send_data and send_file

Remove private def

Added mandatory region and bucket

Enable `Performance/UnfreezeString` cop

The 'setup' section was misleadingly leaving out :bucket and :region in the sample, but servers don't start without them.

In Ruby 2.3 or later, `String#+@` is available and `+@` is faster than `dup`.

```ruby
# frozen_string_literal: true

require "bundler/inline"

gemfile(true) do
  source "https://rubygems.org"

  gem "benchmark-ips"
end

Benchmark.ips do |x|
  x.report('+@') { +"" }
  x.report('dup') { "".dup }
  x.compare!
end
```

```
$ ruby -v benchmark.rb
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux]
Warming up --------------------------------------
                  +@   282.289k i/100ms
                 dup   187.638k i/100ms
Calculating -------------------------------------
                  +@      6.775M (± 3.6%) i/s -     33.875M in   5.006253s
                 dup      3.320M (± 2.2%) i/s -     16.700M in   5.032125s

Comparison:
                  +@:  6775299.3 i/s
                 dup:  3320400.7 i/s - 2.04x  slower

```

Before this change this test was passing even if we revert #31135. The
reason for that is that `app 'development'` will load the environment in
the test process and it is happening before db_create_and_drop is
called.

This was not asserting that the environment was loaded in the db:create
task itself.

To test it we enhance the db:create task with a block that writes to a
tmp file the value of the config. If the environment is loaded before
that task enhancement runs the content of the file will have "true"
insteand of "false".

Let escape_javascript handle conversion to string

This brings `escape_javascript` in line with the behavior of `json_escape` and
allows other value types to be output without needing explicit casting in the
view template.

Example:

    <%= javascript_tag do %>
      var locale = '<%== j I18n.locale %>'; // locale is a symbol
    <% end %>

[close #33907] Error when using "recyclable" cache keys with a store that does not support it

Replace line items with chapters [ci skip]

Line items are a holdover from when orders were used in the examples
instead of books.

Add missing test case for `redirect_to` when request includes a port.

[ci skip] document collection_caching.rb

- Moving the `supports_cache_versioning?` check to a class method. 
- Shorten the method doc. 
- Expand on the error message.

Fix missing curly brace in documentation