build: remove testing.sh in favor of runit.sh; add claude.md reference

Replace inline boot testing with standalone runit.sh runner for clarity:
- Remove scripts/lib/testing.sh source and boot_tests stage from build.sh
- Remove --skip-tests option from build.sh and rebuild-after-zinit.sh
- Update all docs to reference runit.sh for QEMU/cloud-hypervisor testing
- Add comprehensive claude.md as AI assistant entry point with guidelines

Testing is now fully decoupled from build pipeline; use ./runit.sh for
QEMU/cloud-hypervisor validation after builds complete.

README.md

@@ -103,8 +103,7 @@ zosbuilder/
 │   │   ├── alpine.sh       # Alpine operations
 │   │   ├── components.sh   # source building
 │   │   ├── initramfs.sh    # assembly & optimization
-│   │   ├── kernel.sh       # kernel building
-│   │   └── testing.sh      # QEMU/cloud-hypervisor
+│   │   └── kernel.sh       # kernel building
 │   ├── build.sh            # main orchestrator
 │   └── clean.sh            # cleanup script
 ├── initramfs/              # build output (generated)
@@ -250,28 +249,32 @@ Services are migrated from existing `configs/zinit/` directory with proper initi
 
 ### QEMU Testing
 ```bash
-# Boot test with QEMU
-./scripts/test.sh --qemu
+# Boot test with QEMU (default)
+./runit.sh
 
-# With serial console
-./scripts/test.sh --qemu --serial
+# With custom parameters
+./runit.sh --hypervisor qemu --memory 2048 --disks 3
 ```
 
 ### cloud-hypervisor Testing
 ```bash
 # Boot test with cloud-hypervisor
-./scripts/test.sh --cloud-hypervisor
+./runit.sh --hypervisor ch
+
+# With disk reset
+./runit.sh --hypervisor ch --reset --disks 5
 ```
 
-### Custom Testing
+### Advanced Options
 ```bash
-# Manual QEMU command
-qemu-system-x86_64 \
-  -kernel dist/vmlinuz.efi \
-  -m 512M \
-  -nographic \
-  -serial mon:stdio \
-  -append "console=ttyS0,115200 console=tty1 loglevel=7"
+# See all options
+./runit.sh --help
+
+# Custom disk size and bridge
+./runit.sh --disk-size 20G --bridge zosbr --disks 4
+
+# Environment variables
+HYPERVISOR=ch NUM_DISKS=5 ./runit.sh
 ```
 
 ## Size Optimization
@@ -321,7 +324,7 @@ jobs:
     - name: Build
       run: ./scripts/build.sh
     - name: Test
-      run: ./scripts/test.sh --qemu
+      run: ./runit.sh --hypervisor qemu
 ```
 
 ## Advanced Usage
@@ -432,13 +435,16 @@ export DEBUG=1
 
 ```bash
 # Setup development environment
-./scripts/setup-dev.sh
+./scripts/dev-container.sh start
 
-# Run tests
-./scripts/test.sh --all
+# Run incremental build
+./scripts/build.sh
 
-# Check size impact
-./scripts/analyze-size.sh --compare
+# Test with QEMU
+./runit.sh --hypervisor qemu
+
+# Test with cloud-hypervisor
+./runit.sh --hypervisor ch
 ```
 
 ## License