⏲️ feat(nd): Hyperfocus Timer — gentle ND-safe work/break cycles in Mission Control

[welshDog]

⏲️ What This PR Does

Adds the Hyperfocus Timer — audit Feature #5 from the neurodivergent IDE roadmap.

Gentle, non-jarring work/break cycles designed specifically for ADHD brains. No forced interruptions. No aggressive alerts. Just a calm, persistent nudge that respects your flow state.

✅ 26/26 tests passing. Build clean. 0 axe violations.

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📦 Files Added / Changed

File	Purpose
lib/hyperfocus.ts	State machine + helpers — timer logic, phase transitions, presets
components/HyperfocusTimer.tsx	UI widget — non-modal, keyboard navigable, ARIA compliant
app/page.tsx	Integrated into Mission Control top grid (next to Cognitive Load Meter)
__tests__/hyperfocus.test.ts	State transition + cycle completion unit tests

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🎯 Three ND-Tuned Presets

Preset	Focus	Break	Cycles	Best For
⚡ Micro	10 min	2 min	×3	Task initiation, low energy days
🎯 Standard	25 min	5 min	×4	Default ADHD-friendly Pomodoro
🦅 Deep	45 min	10 min	×3	Full hyperfocus flow sessions

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✨ Key Behaviours

• Non-modal — never blocks the screen or interrupts with popups
• aria-live="assertive" — screen reader announces phase transitions (focus→break, break→focus, session complete)
• Start / Pause / Reset controls — fully keyboard navigable
• Cycle tracking — shows current cycle out of total (e.g. "Cycle 2 of 4")
• localStorage persistence — survives page refresh mid-session
• Sensory-theme aware — uses --hc-color-* CSS vars, adapts to CALM/FOCUS/ENERGISE
• Cognitive Load Meter integration — timer state visible alongside load score

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🧪 Test Coverage

npm -C agents/dashboard test
# 26/26 passing ✅
# New tests:
# - Timer starts in idle state with correct preset values
# - Phase transitions: focus → break → focus correctly
# - Cycle counter increments on break→focus transition
# - Session completes after all cycles exhaust
# - Reset returns to idle with original preset
# - Pause/resume preserves remaining time

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🧠 ND Design Rationale

"As an ADHD developer who hyperfocuses for 6 hours without eating, I want gentle, non-jarring reminders that respect my flow state but protect my body."

• No audio by default — auditory sensitivity support
• No flashing — WCAG 2.3.1 compliant
• Subtle border pulse on phase change — only if prefers-reduced-motion is NOT set
• Session complete announcement is assertive — important enough to interrupt, rare enough not to annoy

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🔮 What's Next

• 💻 Brain Dump → Task Chunker — AI micro-task generator
• 🔌 PLUGIN-001 — ND plugin SDK docs + manifest validator
• 📊 Grafana panel — pipe session history into nightly wellbeing dashboard

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⏲️ Audit Feature #5 — HyperCode V2.0 Neurodivergent IDE remediation plan.