Add Reporting and Network Error Observability Hooks

[FlorianRappl]

Proposal

Introduce a lightweight reporting surface for collecting browser-like diagnostics in automation contexts.

Scope:

• Add API hooks for reporting events and network error signals.
• Allow configurable sinks for captured reports.
• Provide filtering by type and endpoint.
  Technical Notes:
• Reporting backend should be injected for storage/forwarding.
• Keep event model minimal and deterministic.
  Acceptance Criteria:
• Reports can be emitted, enumerated, and flushed.
• Network error events can be captured from requester pipeline.
• Tests validate schema shape and filtering behavior.
  Out of Scope:
• Full browser reporting policy implementation.
• Full CSP/NEL parity on first release.

Description

Add reporting/observability hooks for browser-like diagnostics, including structured report emission and network-error-related capture points.

Background

Automation and headless deployments benefit from centralized diagnostics. A lightweight reporting layer improves debuggability without requiring full browser reporting-policy parity.

Specification

• Reporting API: https://w3c.github.io/reporting/
• NEL (background reference for network error reporting concepts): https://www.w3.org/TR/network-error-logging/