build: upgrade dependencies (#230)

* build: upgrade dependencies

* ci: build from php 8.4

* ci: build from php 8.4

tweak: drop scrutinizer

fix: null-safe check of query string key closes #226 (#227)

* fix: null-safe check of query string key
closes #226

* tweak: remove non-existent test

* ci: add codecov token

* ci: add codecov slug

* ci: tweak slug

build: bump version

build: hint version for cyclic dependency with GT/Input

Send debug header showing where the redirect was made (#223)

* feature: send debug header
closes #222

* tweak: fix phpstan errors

* tweak: defensive maximum attempts

* tweak: improve static analysis

* build: update dependencies

* build: php 8.1 compatibility

* ci: specify phpunit version

* ci: specify phpstan version

* ci: specify phpstan version

* ci: quick fix for stream uri

feature: async response methods for #220 (#221)

* feature: async response methods for #220

* build: build with 8.1 compatibility

* tweak: allow more public methods

tweak: internal status code could be null

Upload files using FormData (#214)

* wip: add formdata class

* wip: add urlsearchparams class

* feature: implement URLSearchParams

* feature: tweak urlsearchparams

* wip: extract KeyValuePairStore

* wip: implement KeyValuePairStore for FormData

* wip: improve tests by expecting warning to be emitted

* wip: empty formdata options

* wip: test submitter is included in the form submission

* wip: test constructing with square brackets

* wip: fix static analysis error on DOMNodeList

* wip: implement form types

* wip: remove unused constants

* feature: implement promise-based functions
closes #208

* test: improve static tests

* wip: uploading of files for #213

Formdata, URLSearchParams (#212)

* wip: add formdata class

* wip: add urlsearchparams class

* feature: implement URLSearchParams

* feature: tweak urlsearchparams

* wip: extract KeyValuePairStore

* wip: implement KeyValuePairStore for FormData

* wip: improve tests by expecting warning to be emitted

* wip: empty formdata options

* wip: test submitter is included in the form submission

* wip: test constructing with square brackets

* wip: fix static analysis error on DOMNodeList

* wip: implement form types

* wip: remove unused constants

* feature: implement promise-based functions
closes #208

* test: improve static tests