feat: implement Pomodoro focus timer and WHO-based health reminders

[sohamdalwadi]

Overview

This PR introduces two major productivity and wellness features to the QBIT firmware: a classic Pomodoro Focus Timer and a customizable WHO-guided Health Reminder System. Both systems are integrated into the main state machine, utilizing custom display rendering, distinct buzzer melodies, persistent storage, and (for reminders) a web dashboard configuration panel.

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Commit 1: Pomodoro Focus Timer (pomodoro_ui.h / pomodoro_ui.cpp)

Introduces a focus tracking loop based on the classic Pomodoro productivity technique:

• Structured Intervals:
  • Focus Period: 25 minutes of uninterrupted work.
  • Short Break: 5 minutes of rest.
  • Long Break: 15–30 minutes of rest (triggered automatically after 4 completed focus sessions).
• Visual Interface: Draws a dynamic progress timer inside a custom frame styled explicitly as "Focus Time" on the OLED display.
• Interactive Controls: Integrated single-tap, double-tap, and long-press gestures to start, pause, reset, or exit the timer loop.
• Acoustic Cues: Uses specific buzzer tones to cleanly signal transitions between focus periods and breaks.

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Commit 2: Health Reminder System (reminder.h / reminder.cpp / /data / web_dashboard.cpp)

Implements an interactive health reminder framework adhering to WHO guidelines to maintain well-being throughout the day:

1. Core Logic & Defaults

• 💧 Drink Water: Alerts trigger at 2-hour intervals during the active daytime window (08:00–22:00) to ensure proper daily hydration.
• 🍽️ Meals: Triggers fixed alerts for daily nutrition (Breakfast 08:00, Lunch 13:00, and Dinner 19:00). Includes daily state tracking to guarantee meals alert exactly once per day.
• 💊 Medicine / Pills: Triggers periodic alerts defaulting to 8-hour intervals between 08:00 and 22:00.
• Embedded Assets: Features three custom 48x48 monochrome XBM bitmaps representing water drops, plates, and capsules.

2. Display, Melody, & Control Integration

• Display State: Reminders trigger a 5-second REMINDER_DISPLAY overlay with custom icons and labels. Checking only occurs during idle (GIF_PLAYBACK) to avoid interrupting games or Pomodoro focus sessions.
• Audible Alerts: Plays a repeating, rhythmic REMINDER_TICK_MELODY (short alarm ticks) that auto-mutes after 5 seconds or instantly upon a screen tap.
• On-Device Settings: Adds toggles (Water Rmd, Food Rmd, Pills Rmd) to the scrollable Settings menu with persistent NVS storage (qbitRem).

3. Dashboard Web UI & REST API

• REST Endpoints: Exposes GET /api/reminders and POST /api/reminders to query and save interval configuration.
• Web Config UI: Added a collapsible Health Reminders card to index.html and script.js inside /data, allowing configuration of time bounds, meal times, and intervals directly from the browser.

[sohamdalwadi]

@SeanChangX Added 2 new feature to QBIT