feat: discover uv-managed global Python installations

[Karthik Nadig (karthiknadig)]

The pet-uv locator only discovered uv project/workspace virtual environments (.venv with pyvenv.cfg). Python versions installed globally via uv python install were not discovered by the Uv locator.

Changes

• Scan the uv Python install directory (UV_PYTHON_INSTALL_DIR, or platform defaults: %APPDATA%\uv\python on Windows, ~/.local/share/uv/python on Unix)
• Enumerate subdirectories matching uv's naming convention (cpython-X.Y.Z-os-arch-libc)
• Skip symlinks (Unix) and junctions (Windows) to avoid duplicating minor-version aliases
• Identify executables under the uv install directory via try_from()
• Parse version from directory names with validation (minimum X.Y format)
• Pass Environment to Uv::from() for env var access

Fixes #379

[github-actions]

Performance Report (Linux) ➖

Metric	PR (P50)	PR (P95)	Baseline (P50)	Delta	Change
Server Startup	1ms	1ms	1ms	0ms	0%
Full Refresh	80ms	278ms	80ms	0ms	0%

Results based on 10 iterations. P50 = median, P95 = 95th percentile.

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Legend

• 🚀 Significant speedup (>100ms faster)
• ✅ Faster than baseline
• ➖ No significant change
• 🔺 Slower than baseline (>100ms)
• ⚠️ Significant slowdown (>500ms)

[github-actions]

Test Coverage Report (Linux)

Metric	Value
Current Coverage	65.6%
Base Branch Coverage	65.2%
Delta	.4% ✅

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Coverage increased! Great work!

[github-actions]

Test Coverage Report (Windows)

Metric	Value
Current Coverage	61.75%
Base Branch Coverage	61.28%
Delta	0.47% ✅

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Coverage increased! Great work!

[github-actions]

Performance Report (Windows) ➖

Metric	PR (P50)	PR (P95)	Baseline (P50)	Delta	Change
Server Startup	10ms	13ms	9ms	1ms	11.1%
Full Refresh	167ms	1962ms	147ms	20ms	13.6%

Results based on 10 iterations. P50 = median, P95 = 95th percentile.

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Legend

• 🚀 Significant speedup (>100ms faster)
• ✅ Faster than baseline
• ➖ No significant change
• 🔺 Slower than baseline (>100ms)
• ⚠️ Significant slowdown (>500ms)

[github-actions]

Performance Report (macOS)

Metric	PR (P50)	PR (P95)	Baseline (P50)	Delta
Server Startup	97ms	685ms	83ms	14ms
Full Refresh	190ms	36677ms	137ms	53ms

Results based on 10 iterations. P50 = median, P95 = 95th percentile.

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Legend

• 🚀 Significant speedup (>100ms faster)
• ✅ Faster than baseline
• ➖ No significant change
• 🔺 Slower than baseline (>100ms)
• ⚠️ Significant slowdown (>500ms)