🧪 test: add @wip tag for focused development

- Add @wip tag documentation to BDD_TAGS.md
- Modify all feature test suites to include @wip in tag filters
- Update test scripts to handle @wip tag inclusion
- @wip overrides exclusion tags (@todo, @skip, @flaky) for active development

Generated by Mistral Vibe.
Co-Authored-By: Mistral Vibe <vibe@mistral.ai>

features/greet/greet_test.go

@@ -24,7 +24,7 @@ func TestGreetBDD(t *testing.T) {
 			Strict:        true,
 			Randomize:     -1,
 			StopOnFailure: true,
-			Tags:          "~@flaky && ~@todo && ~@skip",
+			Tags:          "~@flaky && ~@todo && ~@skip && @wip",
 		},
 	}