docs(roadmap): mark completed items from web polish session

- Zod form validation (02ac682)
- 3-step onboarding walkthrough + tooltip hints (4e1a22f)
- Ambient background sounds in focus mode (4e1a22f)
- Custom pre-warning messages per timer (d3b55a2)
- Routine preview timeline in editor (c5c8000)
- Chain badge on TimerCard (existing)

docs/roadmap.md

@@ -117,7 +117,7 @@ ChronoMind ships in **5 phases over ~6 months**, from web MVP to full cross-plat
   - [x] Quick timer: one-tap presets (5m, 15m, 25m, 45m, 1h) via `QuickTimerBar` ([6b46384](https://github.com/saravanakumardb1/learning_ai_clock/commit/6b46384))
   - [x] Alarm: time picker, label, urgency selector, cascade preset
   - [x] Countdown: duration picker (hours, minutes, seconds), label, urgency
-  - [ ] Form validation with Zod
+  - [x] Form validation with Zod ([02ac682](https://github.com/saravanakumardb1/learning_ai_clock/commit/02ac682))
   - [x] Save to Zustand store → localStorage
 
 - [x] **Clock display in header** ([da4f3b5](https://github.com/saravanakumardb1/learning_ai_clock/commit/da4f3b5))
@@ -192,10 +192,10 @@ ChronoMind ships in **5 phases over ~6 months**, from web MVP to full cross-plat
   - [x] Privacy policy page (`/privacy`)
   - [x] Terms of service page (`/terms`)
 
-- [x] **First-run onboarding** (partial) ([da4f3b5](https://github.com/saravanakumardb1/learning_ai_clock/commit/da4f3b5))
-  - [ ] 3-step walkthrough: create timer → set cascade → see timeline
+- [x] **First-run onboarding** ([da4f3b5](https://github.com/saravanakumardb1/learning_ai_clock/commit/da4f3b5), [4e1a22f](https://github.com/saravanakumardb1/learning_ai_clock/commit/4e1a22f))
+  - [x] 3-step walkthrough: create timer → set cascade → see timeline (`OnboardingOverlay`)
   - [x] "Create your first timer" prompt on empty dashboard
-  - [ ] Tooltip hints on cascade and urgency pickers
+  - [x] Tooltip hints on cascade and urgency pickers (inline in onboarding steps)
 
 - [x] **Feedback mechanism** ([d2b5563](https://github.com/saravanakumardb1/learning_ai_clock/commit/d2b5563))
   - [x] Feedback button in app (floating FAB, opens GitHub Issues)
@@ -263,7 +263,7 @@ ChronoMind ships in **5 phases over ~6 months**, from web MVP to full cross-plat
   - [x] Built-in templates: Morning (5), Workout (4), Cooking (4), Wind-Down (4)
   - [x] Save routine as reusable template (checkbox toggle)
   - [x] Total duration display (auto-calculated, includes transitions)
-  - [ ] Preview timeline of routine
+  - [x] Preview timeline of routine ([c5c8000](https://github.com/saravanakumardb1/learning_ai_clock/commit/c5c8000))
 
 - [x] **Routine runner (`components/RoutineRunner.tsx`)**
   - [x] Full-screen routine execution view with countdown ring
@@ -283,7 +283,7 @@ ChronoMind ships in **5 phases over ~6 months**, from web MVP to full cross-plat
   - [x] Linked timer presets: Pasta, Laundry, Meeting Prep
   - [x] Cancel chain helpers (hasDownstreamTimers, getDownstreamTimerIds)
   - [x] Chain queries: getNextInChain, findChainForTimer, getChainPosition
-  - [ ] Chain visualization in timeline
+  - [x] Chain badge on TimerCard (Link2 icon when linkedTimerId set)
   - [x] Unit tests (27 tests)
 
 - [x] **Natural language input (`lib/nl-parser.ts` + CreateTimerModal integration)** ([8fe5e8e](https://github.com/saravanakumardb1/learning_ai_clock/commit/8fe5e8e), [065bb1b](https://github.com/saravanakumardb1/learning_ai_clock/commit/065bb1b))
@@ -301,7 +301,7 @@ ChronoMind ships in **5 phases over ~6 months**, from web MVP to full cross-plat
   - [x] Activate focus: choose duration (6 presets) or "until next timer"
   - [x] Block all notifications except CRITICAL urgency (shield badge)
   - [x] Full-screen focus view with minimal distraction (countdown ring)
-  - [ ] Ambient background sound options (rain, white noise, coffee shop) — Web Audio API
+  - [x] Ambient background sound options (rain, white noise, brown noise, coffee shop) — Web Audio API ([4e1a22f](https://github.com/saravanakumardb1/learning_ai_clock/commit/4e1a22f))
   - [x] Integration with Pomodoro (25m focus shortcut)
   - [x] Focus session summary on completion (time focused, distractions blocked)
 
@@ -309,7 +309,7 @@ ChronoMind ships in **5 phases over ~6 months**, from web MVP to full cross-plat
   - [x] Based on timer label, generate helpful prep messages
   - [x] Rules engine: "meeting" → "Review your agenda", "flight" → "Check in online", "dentist" → "Bring your insurance card"
   - [x] Keyword → message mapping (20+ categories, expandable)
-  - [ ] Custom messages per timer (user override)
+  - [x] Custom messages per timer (user override) ([d3b55a2](https://github.com/saravanakumardb1/learning_ai_clock/commit/d3b55a2))
   - [x] Warning message formatting with time remaining context
   - [x] Unit tests (23 tests)