Url-encode OAuth2 query parameters in Android, Apple and Unity #2019

Tracks PR #2018.

Plan

Goal: Encode OAuth2/GET query parameter keys and values so &, +, #, and = inside a value (e.g. OAuth2 state, a success URL with a query or fragment) are not split, decoded to a space, or truncated.

What changes:

• templates/android/library/src/main/java/io/package/services/Service.kt.twig — Uri.encode on keys/values when building OAuth2 apiQuery
• templates/apple/Sources/Client.swift.twig and templates/swift/Sources/Client.swift.twig — rewrite parametersToQueryString to percent-encode per RFC 3986 unreserved set, join with &
• templates/dotnet/Package/Extensions/Extensions.cs.twig — Uri.EscapeDataString per key/value in ToQueryString (covers Unity + .NET)
• mock-server/app/http.php + tests/resources/spec-openapi3.json — new GET /v1/mock/tests/general/query (general.getQuery) that rejects anything but value=a&b+c#d=e%f and values=[a&b, c+d#e]
• tests/e2e/Base.php — QUERY_ENCODING_RESPONSES; wired into Apple/Swift/.NET/Unity e2e suites and language tests (Tests.swift / Tests.cs). Android OAuth2 URL is browser-redirect-only, so no Android e2e line.

Remaining steps: The linked PR is the full change.

Done when:

• PR fix: url-encode OAuth2 query parameters in Android, Apple and Unity #2018 merged
• Query values with &, +, # reach the mock intact on Apple, Swift, .NET, and Unity e2e