[Ignaciobrenas]

Resolves full verification, accessibility, fuzzing, and CI pipeline parity ahead of v1.0.0 release.

• Adds descriptive commit-row aria-label, tabIndex, and aria-selected (Refs [A11y] Full Keyboard Navigation and Screen Reader ARIA Semantics for DAG Graph #5)
• Upgrades scripts/verify-responsive.js to 4x4x4 themes x views x breakpoints with WCAG 2.1 AA checks (Refs [Testing] Suite Webview E2E multi-breakpoint/temas y Property-Based Fuzzing para GitFsReader, SSH y DAG #18)
• Adds test/fuzzTests.ts (1,050 seeded fuzzing iterations) and fixes IssueBranchLinker.createSlug leading hyphens (Refs [Testing] Suite Webview E2E multi-breakpoint/temas y Property-Based Fuzzing para GitFsReader, SSH y DAG #18)
• Adds test/mcpE2eTests.ts (real temp Git repo stdio + HTTP/SSE E2E) and scripts/benchmark-50k.js, fixing GraphLayout converging-lane O(N^2) memory growth down to 27.88 ms / 37.64 MB (Refs [Testing] Suite E2E completa del servidor MCP (Stdio + HTTP/SSE) y Benchmarks 50k commits #19)
• Adds scripts/run-e2e-smoke.js, package.json test:e2e/benchmark scripts, CI pipeline updates, and Suite 50 (Refs [CI/CD] Add Automated End-to-End (E2E) Smoke & Integration Tests with @vscode/test-electron #2)