Update dependency rack to v3.2.0 (#634)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [rack](https://redirect.github.com/rack/rack)
([changelog](https://redirect.github.com/rack/rack/blob/main/CHANGELOG.md))
| `3.1.16` -> `3.2.0` |
[![age](https://developer.mend.io/api/mc/badges/age/rubygems/rack/3.2.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/rubygems/rack/3.1.16/3.2.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>rack/rack (rack)</summary>

###
[`v3.2.0`](https://redirect.github.com/rack/rack/blob/HEAD/CHANGELOG.md#320---2025-07-31)

[Compare
Source](https://redirect.github.com/rack/rack/compare/v3.1.16...v3.2.0)

This release continues Rack's evolution toward a cleaner, more efficient
foundation while maintaining backward compatibility for most
applications. The breaking changes primarily affect deprecated
functionality, so most users should experience a smooth upgrade with
improved performance and standards compliance.

##### SPEC Changes

- Request environment keys must now be strings.
([#&#8203;2310](https://redirect.github.com/rack/rack/issues/2310),
\[[@&#8203;jeremyevans](https://redirect.github.com/jeremyevans)])
- Add `nil` as a valid return from a Response `body.to_path`
([#&#8203;2318](https://redirect.github.com/rack/rack/pull/2318),
\[[@&#8203;MSP-Greg](https://redirect.github.com/MSP-Greg)])
- `Rack::Lint#check_header_value` is relaxed, only disallowing CR/LF/NUL
characters.
([#&#8203;2354](https://redirect.github.com/rack/rack/pull/2354),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])

##### Added

- Introduce `Rack::VERSION` constant.
([#&#8203;2199](https://redirect.github.com/rack/rack/pull/2199),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])
- `ISO-2022-JP` encoded parts within MIME Multipart sections of an HTTP
request body will now be converted to `UTF-8`.
([#&#8203;2245](https://redirect.github.com/rack/rack/pull/2245),
[@&#8203;nappa](https://redirect.github.com/nappa))
- Add `Rack::Request#query_parser=` to allow setting the query parser to
use. ([#&#8203;2349](https://redirect.github.com/rack/rack/pull/2349),
\[[@&#8203;jeremyevans](https://redirect.github.com/jeremyevans)])
- Add `Rack::Request#form_pairs` to access form data as raw key-value
pairs, preserving duplicate keys.
([#&#8203;2351](https://redirect.github.com/rack/rack/pull/2351),
\[[@&#8203;matthewd](https://redirect.github.com/matthewd)])

##### Changed

- Invalid cookie keys will now raise an error.
([#&#8203;2193](https://redirect.github.com/rack/rack/pull/2193),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])
- `Rack::MediaType#params` now handles empty strings.
([#&#8203;2229](https://redirect.github.com/rack/rack/pull/2229),
\[[@&#8203;jeremyevans](https://redirect.github.com/jeremyevans)])
- Avoid unnecessary calls to the `ip_filter` lambda to evaluate
`Request#ip`
([#&#8203;2287](https://redirect.github.com/rack/rack/pull/2287),
\[[@&#8203;willbryant](https://redirect.github.com/willbryant)])
- Only calculate `Request#ip` once per request
([#&#8203;2292](https://redirect.github.com/rack/rack/pull/2292),
\[[@&#8203;willbryant](https://redirect.github.com/willbryant)])
- `Rack::Builder` `#use`, `#map`, and `#run` methods now return `nil`.
([#&#8203;2355](https://redirect.github.com/rack/rack/pull/2355),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])
- Directly close the body in `Rack::ConditionalGet` when the response is
`304 Not Modified`.
([#&#8203;2353](https://redirect.github.com/rack/rack/pull/2353),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])
- Directly close the body in `Rack::Head` when the request method is
`HEAD`([#&#8203;2360](https://redirect.github.com/rack/rack/pull/2360),
[@&#8203;skipkayhil](https://redirect.github.com/skipkayhil))

##### Deprecated

- `Rack::Auth::AbstractRequest#request` is deprecated without
replacement.
([#&#8203;2229](https://redirect.github.com/rack/rack/pull/2229),
\[[@&#8203;jeremyevans](https://redirect.github.com/jeremyevans)])
- `Rack::Request#parse_multipart` (private method designed to be
overridden in subclasses) is deprecated without replacement.
([#&#8203;2229](https://redirect.github.com/rack/rack/pull/2229),
\[[@&#8203;jeremyevans](https://redirect.github.com/jeremyevans)])

##### Removed

- `Rack::Request#values_at` is removed.
([#&#8203;2200](https://redirect.github.com/rack/rack/pull/2200),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])
- `Rack::Logger` is removed with no replacement.
([#&#8203;2196](https://redirect.github.com/rack/rack/pull/2196),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])
- Automatic cache invalidation in `Rack::Request#{GET,POST}` has been
removed.
([#&#8203;2230](https://redirect.github.com/rack/rack/pull/2230),
\[[@&#8203;jeremyevans](https://redirect.github.com/jeremyevans)])
- Support for `CGI::Cookie` has been removed.
([#&#8203;2332](https://redirect.github.com/rack/rack/pull/2332),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])

##### Fixed

- `Rack::RewindableInput::Middleware` no longer wraps a nil input.
([#&#8203;2259](https://redirect.github.com/rack/rack/pull/2259),
[@&#8203;tt](https://redirect.github.com/tt))
- Fix `NoMethodError` in `Rack::Request#wrap_ipv6` when
`x-forwarded-host` is empty.
([#&#8203;2270](https://redirect.github.com/rack/rack/pull/2270),
[@&#8203;oieioi](https://redirect.github.com/oieioi))
- Fix the specification for `SERVER_PORT` which was incorrectly
documented as required to be an `Integer` if present - it must be a
`String` containing digits only.
([#&#8203;2296](https://redirect.github.com/rack/rack/pull/2296),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])
- `SERVER_NAME` and `HTTP_HOST` are now more strictly validated
according to the relevant specifications.
([#&#8203;2298](https://redirect.github.com/rack/rack/pull/2298),
\[[@&#8203;ioquatix](https://redirect.github.com/ioquatix)])
- `Rack::Lint` now disallows `PATH_INFO="" SCRIPT_NAME=""`.
([#&#8203;2298](https://redirect.github.com/rack/rack/issues/2307),
\[[@&#8203;jeremyevans](https://redirect.github.com/jeremyevans)])

</details>

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Gemfile.lock

@@ -58,7 +58,7 @@ GEM
     prism (1.4.0)
     public_suffix (6.0.1)
     racc (1.8.1)
-    rack (3.1.16)
+    rack (3.2.0)
     rackup (2.2.1)
       rack (>= 3)
     rainbow (3.1.1)