automated accessibility checks (#208)

* initial add-accessibility-tests proposal

* refactor example minimal site to follow standard index.md pattern

* adjust proposal scope to only work on validating theme not site content

* phase 3 tasks

* update to phase 4 (color contrast) requirements

* initial phase 4 color contrast implementation

* refactor for test code readability

* test on search enabled site

* test for color contrast in links

* link contrast test updates

* more color contrast tests

* ghost button test

* refactor site building helpers to reduce duplicated code

* only build a test site once and cache

* removed tests which were not failing appropriately

* notes

* remove debug output

* remove unused functions

* removed unused test helper classes

* flake fixes

* refactor accessibility test suite fixtures to main conftest

* rename test to indicate that it is only testing the search modal, not all modals

* rename tests because it is testing font color vs background (text) not a link color

* new test case to check code block contrast

* test case to verify contrast in top nav

* document known issues

* add links

* new test cases to check text contrast on button elements

* add failure details

* formatting, future work

* test for bug in parser

* fallback should use combined palette + terminal values

* xfail known issues

* note to update docs

* revert search modal changes and skip related tests, theme fix to be added in separate PR

* test to verify that default palettes are tested

* update code coverage report

* regen coverage

* removed openspec scratch work artifacts, update refactor document with current progress

* update test results

* bump theme

Author: ntno

Makefile

@@ -88,7 +88,13 @@ quick-tests:
 
 #for developer use, assumes you have already installed prereqs
 generate-test-coverage:
-	pytest --cov=terminal --cov-branch --cov-report=html tests/
+	pytest \
+		--cov=terminal \
+ 		--cov=tests/interface \
+		--cov=tests/utils \
+        --cov=tests/accessibility \
+        --cov-branch \
+        --cov-report=html && \
 	rm -rf documentation/docs/about/coverage-report/.gitignore