v0.4.0

• label parameters with explode: false use , between array items, not .
  (#31). RFC 6570 spells the unexploded form .3,4,5 and reserves the repeated
  dot for explode: true; both the parser and the serializer used . in either
  case, so a conforming client's .3,4,5 deserialized to the single element
  "3,4,5" and failed its own schema. Object forms were already correct.

• spaceDelimited and pipeDelimited parameters recognise the percent-encoded
  delimiter (#32). The value was split on a literal ' ' or '|' before
  decoding, but a raw space cannot travel in a URI and | is outside the query
  character set, so any PSR-7 URI implementation delivers %20 / %7C and the
  whole value came back as one element. Both wire forms are now accepted, the
  serializer emits %20 for spaceDelimited, and it rejects a list item that
  contains its own delimiter — the style has no escape for one. That limitation
  holds in both directions: a separator and an encoded item character are the
  same octets on the wire, so color=blue%7Cblack is read as two values and
  never as the single value blue|black.

  Both bugs were symmetric between this package's parser and serializer, so the
  round-trip property could not see them; the styles are now pinned by exact
  wire fixtures taken from the OpenAPI style-examples table.