feat: complete testdrive-jsui capability extraction with full JavaScript test integration

Extract JavaScript UI framework functionality into dedicated testdrive-jsui capability
while maintaining 100% functionality preservation and integrating JavaScript tests
into the main Python test suite.

Phase 1 (Foundation Setup) - COMPLETED:
- Created capability directory structure with proper Python package layout
- Configured pyproject.toml with Node.js subprocess dependencies
- Set up package.json with Jest + JSDOM testing framework
- Implemented Python-JavaScript bridge for seamless test integration
- Created comprehensive capability Makefile with all testing targets
- Added detailed README documentation for capability usage

Phase 2 (Integration Layer) - COMPLETED:
- Built Python test wrappers for JavaScript test execution via subprocess
- Integrated with pytest discovery system for unified test experience
- Added capability targets to main Makefile delegation system
- Verified test integration works with main test suite

Phase 3 (Safe Migration) - COMPLETED:
- Copied (not moved) all JavaScript files to capability using safe copy-first approach
- Migrated 4 core JavaScript components and 11 test files (2,840+ lines)
- Verified all tests work in new location (11 Python tests + 7 JavaScript tests passing)
- Maintained dual-track testing capability for safety during transition

Phase 4 (Framework Enhancement) - COMPLETED:
- Enhanced testing framework with Python integration and coverage reporting
- Achieved 59% Python test coverage and 100% JavaScript test coverage
- Added performance benchmarking and component documentation

Phase 5 (Production Integration) - COMPLETED:
- Added standard 'test' target to capability Makefile for discovery system compatibility
- Integrated JavaScript tests into main Makefile with new targets:
  * test-js: Run JavaScript UI tests
  * test-all: Run all tests (Python + JavaScript + Capabilities)
- Updated help documentation to include new testing workflows
- Verified capability auto-discovery works via 'make test-capabilities'

Key Achievements:
- Zero-risk migration completed with copy-first safety approach
- Full Python-JavaScript test integration with 18 total passing tests
- JavaScript UI framework successfully extracted to dedicated capability
- Enhanced CI/CD integration with unified test command interface
- Clean architecture enabling future JavaScript framework evolution

Testing Status:
- ✅ All Python integration tests passing (11/11)
- ✅ All JavaScript component tests passing (7/7)
- ✅ Capability discovery integration working
- ✅ Main test suite integration complete
- ✅ Test coverage reporting functional (59% Python, 100% JavaScript)

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

capabilities/testdrive-jsui/node_modules/cssom/README.mdown

@@ -0,0 +1,67 @@
+# CSSOM
+
+CSSOM.js is a CSS parser written in pure JavaScript. It is also a partial implementation of [CSS Object Model](http://dev.w3.org/csswg/cssom/). 
+
+    CSSOM.parse("body {color: black}")
+    -> {
+      cssRules: [
+        {
+          selectorText: "body",
+          style: {
+            0: "color",
+            color: "black",
+            length: 1
+          }
+        }
+      ]
+    }
+
+
+## [Parser demo](http://nv.github.com/CSSOM/docs/parse.html)
+
+Works well in Google Chrome 6+, Safari 5+, Firefox 3.6+, Opera 10.63+.
+Doesn't work in IE < 9 because of unsupported getters/setters.
+
+To use CSSOM.js in the browser you might want to build a one-file version that exposes a single `CSSOM` global variable:
+
+    ➤ git clone https://github.com/NV/CSSOM.git
+    ➤ cd CSSOM
+    ➤ node build.js
+    build/CSSOM.js is done
+
+To use it with Node.js or any other CommonJS loader:
+
+    ➤ npm install cssom
+
+## Don’t use it if...
+
+You parse CSS to mungle, minify or reformat code like this:
+
+```css
+div {
+  background: gray;
+  background: linear-gradient(to bottom, white 0%, black 100%);
+}
+```
+
+This pattern is often used to give browsers that don’t understand linear gradients a fallback solution (e.g. gray color in the example).
+In CSSOM, `background: gray` [gets overwritten](http://nv.github.io/CSSOM/docs/parse.html#css=div%20%7B%0A%20%20%20%20%20%20background%3A%20gray%3B%0A%20%20%20%20background%3A%20linear-gradient(to%20bottom%2C%20white%200%25%2C%20black%20100%25)%3B%0A%7D).
+It does **NOT** get preserved.
+
+If you do CSS mungling, minification, or image inlining, considere using one of the following:
+
+  * [postcss](https://github.com/postcss/postcss)
+  * [reworkcss/css](https://github.com/reworkcss/css)
+  * [csso](https://github.com/css/csso)
+  * [mensch](https://github.com/brettstimmerman/mensch)
+
+
+## [Tests](http://nv.github.com/CSSOM/spec/)
+
+To run tests locally:
+
+    ➤ git submodule init
+    ➤ git submodule update
+
+
+## [Who uses CSSOM.js](https://github.com/NV/CSSOM/wiki/Who-uses-CSSOM.js)