docs: update README for clarity and structure in test suite documentation

tests/README.md

@@ -1,12 +1,24 @@
-This folder contains a minimal C++ test harness for starworld.
+# Starworld Test Suite
 
-Build target: stardust-tests
+This folder contains the C++ test harness for Starworld.
 
-What it checks:
-- Protocol signature stability: compares NLPacket::computeProtocolVersionSignature() against the expected value for the vendored Overte commit.
-- Domain discovery parsing: validates that JSON containing Vircadia- or Overte-style fields is parsed into host/port pairs correctly.
+## Build Target
 
-Run:
-  ./build/stardust-tests
+`starworld-tests` - Built alongside the main executable
+
+## What It Tests
+
+1. **Protocol signature stability**: Compares `NLPacket::computeProtocolVersionSignature()` against the expected value for the vendored Overte protocol
+2. **Domain discovery parsing**: Validates JSON parsing from Vircadia/Overte metaverse directories into host/port pairs
+
+## Running Tests
+
+```bash
+./build/starworld-tests
+```
 
 Exit code 0 indicates PASS.
+
+## Test Files
+
+- `TestHarness.cpp` - Main test implementation with protocol and discovery tests