Add projected support to parser

[matth-love]

Description

Adds support for projected horizontal + geographic vertical in parser, so now things like this work:

$ transformez info reference EPSG:6636+6321

 Reference:
------------
  ID:                EPSG:6636+6321
  Name:              NAD83(PA11)
  Kind:              ellipsoidal_height
  Axis Direction:    up
  Units:             metre
  No operation binding available for EPSG:6636+6321

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Checklist

• PR title is descriptive
• PR body contains links to related and resolved issues (e.g. closes #1)
• If needed, CHANGELOG.md updated
• If needed, docs and/or README.md updated
• If needed, unit tests added
• All checks passing
• At least one approval

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🔍 Docs preview: https://transformez--171.org.readthedocs.build/en/171/