chore: fork pylon v2 into psylon with EUPL licensing

[kleberbaum]

Summary

This PR forks Pylon v2 into Psylon, sets up the new licensing model (EUPL-1.2 + Apache-2.0 for upstream code), rebrands the docs, and applies the initial package renames.

Canonical repo: https://github.com/netsnek/psylon

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Changes

• Add COPYING and LICENSES/:

  • Project as a whole under EUPL-1.2.

  • Upstream Pylon code remains Apache-2.0 (kept via LICENSES/upstream/Apache-2.0).

  • Minimal SPDX file headers added where missing:

    • Copyright 2024 Nico Schett <nico.schett@cronit.io>
    • SPDX-License-Identifier: Apache-2.0

• Update README:

  • New centered SNEK logo block.
  • Rebrand prose from Pylon → Psylon.
  • Clarify: Psylon is a Pylon v2 fork by Netsnek e. U., stays a GraphQL-based microservice framework, with selective backports from Pylon v3.
  • Add Roadmap focused on GQty + pgqty, linking to
    https://github.com/gqty-dev/gqty/issues/2051.

• Package / import renames:

  • create-pylon → create-psylon
  • @getcronit/pylon → psylon
  • @getcronit/pylon-dev → @netsnek/psylon-dev
  • @getcronit/pylon-builder → @netsnek/psylon-builder
  • @getcronit/pylon-telemetry → @netsnek/psylon-telemetry

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Migration

Update downstream projects to the new package names and CLI:

• @getcronit/pylon → psylon
• @getcronit/pylon-dev → @netsnek/psylon-dev
• @getcronit/pylon-builder → @netsnek/psylon-builder
• @getcronit/pylon-telemetry → @netsnek/psylon-telemetry
• create-pylon → create-psylon

[kleberbaum]

lgtm 🚀