feat: implement modular configurable RGB LED status indicators

[Mathew005]

Description

This PR implements a comprehensive, configurable RGB LED status indicator system for the ESP32-S3 CSI Node. It provides real-time visual feedback on system states (Booting, WiFi Connecting, Connected, and Error) while remaining fully customizable via Kconfig and NVS.

Features

• Modular Driver: Dedicated led_indicator.c driver running as a background FreeRTOS task.
• State Machine:
  • Solid White: System Booting / NVS Initialization.
  • Fast Blinking Blue: WiFi Searching/Connecting.
  • Slow Pulsing Green: WiFi Connected & CSI Streaming.
  • Solid Red: WiFi Connection Failure / Retries Exhausted.
• Full Configurability:
  • Compile-time: CONFIG_RGB_LED_ENABLED and CONFIG_RGB_LED_GPIO (defaults to pin 38).
  • Run-time: Dynamic toggling via NVS (status_led flag).
  • Provisioning: Support added to provision.py via the --status-led flag.

Bug Fixes Included

• Linter Fixes: Resolved Pyre type-checking errors in provision.py for MAC address parsing and NVS binary generation.
• Live Disconnect Hook: Fixed an edge case where the LED stayed green if the WiFi dropped during operation; it now correctly reverts to searching (blue) or error (red).
• Initialization Reset: Fixed an issue where disabling the LED via NVS would leave it latched at the last color; the driver now explicitly clears the hardware state before stopping.

Testing

• Hardware: ESP32-S3 board (COM8).
• Scenarios Verified:
  • --status-led 1: Flawless state transitions from White -> Blue -> Green.
  • Hotspot Drop: Turning off the hotspot immediately triggered the Blinking Blue retry state and eventually Solid Red.
  • --status-led 0: Verified the LED stays completely dark upon boot and throughout operation.
  • MAC Filtering: Verified provision.py still correctly parses and flashes MAC filter binary blobs.

[Mathew005]

Description

This PR introduces an enhanced, fully configurable RGB LED status indicator system for the ESP32-S3 CSI Node. It expands on the existing design to provide real-time visual feedback across multiple subsystems (Booting, WiFi, mmWave, and Swarm) while remaining flexible through NVS configuration and provisioning.

Features

• Unified Driver:
  A modular RGB LED driver implemented as a background FreeRTOS task, responsible for managing all system states in a centralized manner.

• Enhanced State Machine:

  • WiFi:
    • Fast Blinking Blue → Connecting
    • Solid Red → Connection Error / Failure
    • Slow Pulsing Green → Connected & Healthy
  • mmWave Sensor:
    • Slow Blinking Yellow → Sensor detected but failed to initialize
  • Swarm Bridge:
    • Slow Blinking Magenta → Seed unreachable
    • Quick Magenta Flash → Successful data ingest event

• Smart State Handling:
  Error and diagnostic states (mmWave, Swarm) are conditionally evaluated. If a subsystem is not configured or detected, its error state is skipped—ensuring the LED reflects a valid “healthy” (Green) state for partial but functional setups.

• Provisioning Support:
  Extended provisioning via provision.py:

  • --status-led 1/0 for runtime enable/disable
  • Additional flags for Swarm configuration and diagnostics

Testing

• Hardware Integration:
  Verified on ESP32-S3 boards (COM5 and COM8) across both receiver and TDM configurations.

• Failure Resilience:

  • Disabling the Swarm Seed correctly triggers Magenta diagnostic states
  • Disconnecting the mmWave sensor triggers Yellow error indication
  • WiFi failure paths correctly fall back to Red

• Build Validation:
  Successfully compiled and tested in a Docker-based ESP-IDF v5.2 environment.

[ruvnet]

Rebase needed — current main has had multiple firmware/esp32-csi-node changes (Kconfig, CMakeLists, and #273 just merged disabling the onboard WS2812 during CSI collection). Once rebased your modular RGB indicator should sit cleanly on top of the #273 disable logic. Happy to re-review post-rebase.

[Mathew005]

I've rebased the branch onto the latest main.

Here is what was resolved:

Integration with #273: Using conditional compilation (#ifdef CONFIG_RGB_LED_ENABLED), the modular RGB status indicator task claims the LED when enabled. If disabled, it cleanly falls back to the one-shot #273 explicit disable logic to prevent Wi-Fi interference.
Fallbacks: Added a preprocessor fallback for the GPIO pin to guarantee the firmware compiles flawlessly even when the RGB LED subsystem is completely disabled in menuconfig.
Build Validation: Verified that both configurations (LED enabled and disabled) build cleanly in the upgraded ESP-IDF v5.4 environment.