Fix ImportError with lxml==5.2.1 (Cython 3.0)

[Copilot]

In lxml 5.2.1 (Cython 3.0.10), lxml.etree.ElementTree and lxml.etree.Element are compiled as Cython functions rather than Python classes. This breaks two things at import time: the | union type annotation syntax (e.g. ElementTree.ElementTree | None) and isinstance() checks using those names.

Changes

• from __future__ import annotations added to all affected modules (common.py, xtce/calibrators.py, xtce/comparisons.py, xtce/encodings.py, xtce/parameter_types.py, xtce/parameters.py, xtce/validation.py). This defers annotation evaluation to strings, so the | operator is never called on a Cython function at module load time.

• isinstance() fix in xtce/validation.py: replaced isinstance(xml_source, ElementTree.ElementTree) with isinstance(xml_source, ElementTree._ElementTree). _ElementTree is the actual underlying class (available across all supported lxml versions); ElementTree.ElementTree is a Cython function in 5.2.1 and cannot be used as an isinstance target.

• Removed redundant quoted annotations (e.g. -> "Calibrator") that became unnecessary once from __future__ import annotations was added.

# Before (fails at import with lxml 5.2.1):
tree: ElementTree.ElementTree | None  # TypeError: unsupported operand type(s) for |

# After (deferred to string; never evaluated at load time):
from __future__ import annotations
tree: ElementTree.ElementTree | None  # fine

Summary

Fixes a TypeError on import when using lxml==5.2.1 caused by Cython 3.0 changing lxml.etree.ElementTree from a class to a Cython function. The fix uses from __future__ import annotations to avoid runtime evaluation of type annotations, and switches the one isinstance() check to use the concrete _ElementTree class.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.82%. Comparing base (f8dcb04) to head (916a976).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #243   +/-   ##
=======================================
  Coverage   94.81%   94.82%           
=======================================
  Files          48       48           
  Lines        3861     3868    +7     
=======================================
+ Hits         3661     3668    +7     
  Misses        200      200           

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[Copilot]

Pull request overview

This PR fixes import-time failures when using lxml==5.2.1 (Cython 3), where lxml.etree.ElementTree/Element are compiled as Cython functions, breaking |-style union annotations and isinstance() checks.

Changes:

• Added from __future__ import annotations to defer type annotation evaluation in affected modules.
• Updated validate_xtce() to use ElementTree._ElementTree for isinstance() checks (works across supported lxml versions).
• Removed now-redundant quoted return type annotations (e.g., -> "ParameterType").

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
space_packet_parser/common.py	Defers annotations to avoid import-time evaluation issues involving lxml element types; removes redundant quoted annotations.
space_packet_parser/xtce/calibrators.py	Defers annotations and removes redundant quoted annotations in from_xml return types.
space_packet_parser/xtce/comparisons.py	Defers annotations and removes redundant quoted annotations in from_xml return types.
space_packet_parser/xtce/encodings.py	Defers annotations and removes redundant quoted annotations in from_xml return types.
space_packet_parser/xtce/parameter_types.py	Defers annotations and removes redundant quoted annotations in from_xml return types.
space_packet_parser/xtce/parameters.py	Defers annotations and removes redundant quoted annotations in from_xml return types.
space_packet_parser/xtce/validation.py	Fixes isinstance() against ElementTree._ElementTree to avoid TypeError under lxml==5.2.1.