MM-64282 E2E/Playwright: Test documentation format (#31050)

* initial implementation of test documentation in spec file with AI-assisted prompt from Claude and linter script

* update snapshots

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Co-authored-by: Mattermost Build <build@mattermost.com>

.gitignore

@@ -162,5 +162,5 @@ docker-compose.override.yaml
 
 
 **/CLAUDE.local.md
-CLAUDE.md
+./CLAUDE.md