benchmark: publish the first AgentPack vs no-context E2E report

[vishal2612200]

Goal

Run and publish the first dated AgentPack vs no-context E2E outcome report.

Suggested files

• benchmarks/e2e/README.md
• benchmarks/results/YYYY-MM-DD-e2e-ab.md
• docs/benchmarking.md if status changes

Acceptance criteria

• Uses the documented benchmark e2e and benchmark e2e-report workflow.
• Reports task success, validation result, tool calls, token/time proxy if available, and time-to-first-correct-file where measurable.
• Keeps file-selection benchmark claims separate from task-success claims.