Add privacy-preserving telemetry aggregation script

Moves and enhances the telemetry aggregator script to `scripts/agent/telemetry-aggregator.mjs`.
Updates `package.json` to point to the new location.
Implements robust parsing for smoke test summaries and fuzz reports.
Adds PII sanitization (IPs, emails, keys, paths).
Enforces opt-in via `ENABLE_TELEMETRY` environment variable.
Adds `ai/reports/` to `.gitignore`.

.gitignore

@@ -7,3 +7,4 @@ test-results/
 tests/visual/__snapshots__/
 artifacts/
 css/tailwind.generated.css
+ai/reports/