fix: report collector and read failures

[sasan1200]

Summary

• Report collector authorization failures, heartbeat, delivery time, and executable metadata in posture and Doctor.
• Retain safe read-failure categories and recovery timestamps in storage health. Update API contracts and documentation.

Type of Change

• 🐛 Bug fix (non-breaking change which fixes an issue)
• ✨ New feature (non-breaking change which adds functionality)
• 🔒 Security enhancement
• 📝 Documentation update
• 🎨 Refactoring / Code style cleanups

Verification Checklist

• go test ./... passes cleanly
• python3 plugin/hooks/test_secret_guard.py and other python hook tests pass
• bash packaging/swift_macos.sh test --package-path menubar passes
• ./packaging/test/e2e_smoke.sh passes
• No secrets, tokens, or private keys are exposed or committed

Focused race tests, live guard workflow, lint, documentation checks, and the CGO-disabled build passed.

Broad Go tests failed in TestSessionReportIntegerOverflowRejectsPartialTotals, TestContentOverFileBoundKeepsSquashAnswer, and TestContentRewrittenHistoryNamesWhatWasMeasured. The Swift suite failed in five DaemonSupervisorTests; that class passed separately. Python hook suites and packaging smoke were not run for this change. These unresolved checks keep this PR in draft.