refactor(cli): share RAM environment detection

[duyua9]

Description

Move the setup wizard's RAM detection into a reusable CLI environment helper. This keeps the existing openviking-server init RAM-tier recommendations unchanged while making the detection logic available to future environment/doctor checks.

Related Issue

Related to #1436

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactoring (no functional changes)
• Performance improvement
• Test update

Changes Made

• Added openviking_cli.utils.environment.get_system_ram_gb().
• Updated setup_wizard.py to reuse the shared helper for RAM-tier model recommendations.
• Added focused tests for sysconf detection, Windows fallback detection, and failure fallback.

Testing

• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have tested this on the following platforms:
  • Linux
  • macOS
  • Windows

Commands run:

python3 -m pytest -o addopts='' --confcutdir=tests/cli tests/cli/test_environment.py tests/cli/test_setup_wizard.py::TestRAMRecommendations -q
git diff --check

Checklist

• My code follows the project's coding style
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published

Screenshots (if applicable)

N/A

Additional Notes

Full pytest collection was not run because this local environment is missing optional dependencies required by the repository-level test conftest. The scoped CLI tests above avoid that global conftest and cover the changed helper directly.

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PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

🎫 Ticket compliance analysis ✅ 1436 - Fully compliant Compliant requirements: Moved RAM detection to a reusable openviking_cli.utils.environment module

⏱️ Estimated effort to review: 2 🔵🔵⚪⚪⚪

🏅 Score: 95

🧪 PR contains tests

🔒 No security concerns identified

✅ No TODO sections

🔀 No multiple PR themes

⚡ Recommended focus areas for review Overly Broad Exception Catch The Windows fallback uses except Exception: which could suppress unexpected errors. While this preserves existing behavior, it hinders debugging if new failure modes arise. except Exception: pass

[github-actions]

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