[OpenSpec] Doorlooptijd Dashboard — SLA adherence and processing time analytics

[rubenvdlinde]

OpenSpec change: doorlooptijd-dashboard

Evidence-backed proposal from market intelligence (97K requirements, 39K tenders).

Labels: openspec, enhancement

[rubenvdlinde]

Implementation complete in PR #94.

Changes:

• New /doorlooptijd route with SLA analytics dashboard (compliance rate, donut chart by case type, processing time histogram, monthly trend line, at-risk panel, performance table)
• SLA Compliance KPI card added to main dashboard (5th card)
• Doorlooptijd navigation button in dashboard header
• Pure utility functions in doorlooptijdHelpers.js for all SLA calculations
• Date range filter (3m/6m/12m/year/all) and case type filter
• Full OpenSpec lifecycle: proposal, specs (11 requirements), design, tasks (26/26), verify, archive

Branch: feature/89/doorlooptijd-dashboard
PR: #94 (target: development)

[rubenvdlinde]

Implemented and archived via OpenSpec pipeline.