v2: Initial clean branch with unit tests + CI/CD pipeline

- Started from ac75faa (initial E4B-MarkBase integration)
- Kept Sources/ (all engine code) + Package.swift + .gitignore
- Removed all ad-hoc tests, documentation, scripts, Python files
- Added Tests/00_Unit/ (MathTest, TokenizerTest, SamplerTest)
- Added .gitea/workflows/ci.yaml (build + unit tests + lint)
- Added Scripts/check_resources.sh (memory-aware test runner)
- Added Tests/Manifest.json (resource requirements for all tests)
- Focus: 4-bit quantized models only

Scripts/check_resources.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+# check_resources.sh — Check available system memory before running tests
+# Usage: check_resources.sh <required_memory_gb>
+
+set -euo pipefail
+
+REQUIRED_GB="${1:-0}"
+
+# Get available memory using vm_stat on macOS
+if [[ "$(uname)" == "Darwin" ]]; then
+    PAGE_SIZE=$(vm_stat | head -1 | awk '{print $NF}' | sed 's/\.//')
+    FREE_PAGES=$(vm_stat | awk '/free/ {print $NF}' | sed 's/\.//')
+    if [[ -z "$FREE_PAGES" ]]; then
+        FREE_PAGES=$(vm_stat | awk '/Pages free/ {print $3}' | sed 's/\.//')
+    fi
+    AVAILABLE_GB=$(( FREE_PAGES * 16384 / 1073741824 ))  # 16384 = page size on Apple Silicon
+    echo "Available memory: ~${AVAILABLE_GB}GB (free: ${FREE_PAGES} pages)"
+else
+    AVAILABLE_GB=$(free -g | awk '/^Mem:/ {print $7}')
+    echo "Available memory: ~${AVAILABLE_GB}GB"
+fi
+
+if [[ "$AVAILABLE_GB" -lt "$REQUIRED_GB" ]]; then
+    echo "ERROR: Need ${REQUIRED_GB}GB but only ${AVAILABLE_GB}GB available"
+    echo "Run 'memory_pressure' to check memory status"
+    exit 1
+fi
+
+echo "OK: ${AVAILABLE_GB}GB >= ${REQUIRED_GB}GB required"
+exit 0