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Initialize symbols instead of mapping to_sym on the set of strings

The outer router object already keeps a hash of named routes, so we
should just use that.

Small fixes [ci skip]

refactor the tests with a backwards compatible method call so we can rm
add_route2 from the journey router

then we can let the mapping object derive stuff that the Route object
needs.

now that we aren't doing options manipulations, we can just pass the
mapping object down and read values from it.

since we've extracted the `to` initialization, there's no need for
`process_path`

if `to` was initialized, this method would return, so we can eliminate
the to ||= in the conditional.  Finally, let's return a nil in the else
block so that it's explicit that this method can return nil

Eventually we'll pull this up and delete `process_path`.

We don't need a method for something like this.  I want to pull this up
the stack as well and move the module + :controller ArgumentError up the
stack as well

now we don't need to add it to a hash and delete it from the hash later
just to pass it around

`add_route` needs the AST, so rather than shove it in a hash and delete
later, lets move parsing up the stack so we can pass down later

also change the feeler to subclass AD::Request so that it has all the
methods that Request has

Eventually I want to eliminate the FakeSet test class

I'm going to reimplement this using route objects, so it will be easier
if we just change ast access to go through a method rather than hashes

we don't need to keep adding it and deleting if from hashes.

Eventually I want to pull up AST generation so that we don't have to add
it to the `conditions` hash.

Add method_source dependency to activesupport

We already have rake install command that does the same thing.

Remove `version` argument in install.rb

Fix middleware deprecation message. Related to #21172.

[ci skip] SQL is written using statements, not sentences

It just constructs a Path::Pattern object with the AST that it already
has

This was a useless object.  We can just directly construct a
Path::Pattern object without a Strexp object.

the caller already has it, there is no reason to pack it in to an object
and just throw that object away.

we always pass all parameters, so there is no reason to provide default
arguments.

the caller already has access to `as`, so we can stop passing it around.

the same value that is extracted from the options hash earlier is
returned, so we don't need to pass it in in the first place.  The caller
already has the data, so stop passing it around.