cmake: include GNUInstallDirs before install interface paths

[fallintoplace]

Why

CMAKE_INSTALL_INCLUDEDIR could be empty when used in target_include_directories() before GNUInstallDirs is included, causing invalid installed include paths for package consumers.

What changed

• Move include(GNUInstallDirs) to immediately after project() so CMAKE_INSTALL_LIBDIR, CMAKE_INSTALL_BINDIR, and CMAKE_INSTALL_INCLUDEDIR are defined before any usage.

Validation

No tests were run per request.

Summary by CodeRabbit

• Chores
  • Streamlined the build setup for installation paths, making standard install directories available earlier in the configuration process.
  • Removed a redundant configuration step to keep packaging and export handling cleaner and more consistent.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Enterprise

Run ID: b6abf539-c14d-4c7a-8e79-f84fb87e06d9

📥 Commits

Reviewing files that changed from the base of the PR and between 52119ee and d093754.

📒 Files selected for processing (1)

• CMakeLists.txt

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📝 Walkthrough

Walkthrough

The include(GNUInstallDirs) statement in CMakeLists.txt was moved earlier in the file, with the previously later, redundant occurrence removed. No functional or exported entity changes were made.

Changes

CMake Include Reorganization

Layer / File(s)	Summary
Move GNUInstallDirs include earlier CMakeLists.txt	include(GNUInstallDirs) is added earlier in the file with explanatory comments; the duplicate later include before the packaging section is removed.

Estimated code review effort: 1 (Trivial) | ~2 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly matches the change to move GNUInstallDirs earlier so install interface paths are defined before use.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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Warning

⚠️ This pull request shows signs of AI-generated slop (redundant_comments). It has been flagged by CodeRabbit slop detection and should be reviewed carefully.