feat: Apple Silicon support + graph bar color picker

[nastarynaz]

Ran command: git log --oneline origin/master ^williamnie/master 2>/dev/null || git log --oneline gao-sun/master..origin/master 2>/dev/null || git log --oneline b5c3bd0..HEAD
Ran command: git remote -v | grep -v williamnie
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---

Title:

feat: Apple Silicon support + graph bar color picker

Body:

## Summary

This PR brings two major improvements to eul:

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### 🍎 Apple Silicon (M-series) Temperature & GPU Support

**SMC / Temperature fixes:**
- `SMCParamStruct` size corrected for Apple Silicon (prevents misaligned reads)
- Added `FLT` (32-bit float) sensor format support — Apple Silicon uses `FLT` instead of `SP78`. Code now tries `SP78` first and falls back to `FLT`
- Fan speed decoding also updated to fall back to `FLT` (SMCResult 135 handled silently)
- Apple Silicon fallback sensor names in `SmcControl`:
  - CPU Die → `CPU_PCORE`, `CPU_PACKAGE`
  - CPU Proximity → `CPU_ECORE`
  - GPU Proximity → `GPU_APPLE_SILICON`

**GPU fixes:**
- `getGPUs()` uses model name as identifier when `device-id` is absent (Apple Silicon GPUs)
- `getInfo()` falls back to `"apple"` as pciMatch when `IOPCIMatch` unavailable
- GPU usage tries multiple keys: `Device Utilization %`, `GPU Activity(%)`, `GPU Core Utilization`, `IOAcceleratorStatistics2` — defaults to 0 instead of crashing
- CPU usage clamped to prevent occasional 100% spikes on Apple Silicon

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### 🎨 Graph Bar Color Picker

- New `GraphColorOption` enum: Monochrome, Red `#e03a3e`, Blue `#009ddc`, Orange `#f6821f`, Yellow `#fcb827`
- Per-component color stored in `EulComponentConfig`, persisted via `UserDefaults`
- In Preferences → Components, a **Graph Color** row with 5 circle swatches appears when "Show Graph" is ON
- `LineChart` accepts a `color` param (fill at 50% opacity, full stroke)
- `CpuView`, `GpuView`, `MemoryView` all pass the configured color to `LineChart`

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### 🔧 Build & Compatibility
- Minimum deployment target: `10.15 → 11.0` for all targets
- Removed deprecated `SDKROOT=macosx` from build scripts
- GitHub Actions updated to v4, removed hardcoded `-sdk macosx` flag
- Added uptime days display, bumped version to 1.6.3