feat(button): add hys_ctrl_mode for ESP32-P4 GPIO hysteresis support

[diplfranzhoepfinger]

Description

The ESP32-P4 GPIO peripheral supports hardware input hysteresis (SOC_GPIO_SUPPORT_PIN_HYS_FILTER). The ESP-IDF gpio_config_t already exposes the hys_ctrl_mode field for this chip, but the button component never forwarded it — meaning users had no way to enable hysteresis for a GPIO button.

Problem: When a button signal rises or falls slowly through the GPIO switching threshold (e.g. with long cable capacitance or a weak pull resistor), the digital input toggles rapidly around that threshold. This produces a burst of spurious BUTTON_PRESS_DOWN / BUTTON_PRESS_UP events even though the user pressed or released the button only once.

Fix: Add an optional hys_ctrl_mode field to button_gpio_config_t. On ESP32-P4, setting GPIO_HYS_SOFT_ENABLE activates the hardware hysteresis filter before the signal reaches the GPIO input register, eliminating the glitch without any software workaround. The field is guarded by #if SOC_GPIO_SUPPORT_PIN_HYS_FILTER, so the struct layout and ABI are unchanged on all other chips.

Changes:

• components/button/include/button_gpio.h — added #include "driver/gpio.h" and the new hys_ctrl_mode field (behind SOC_GPIO_SUPPORT_PIN_HYS_FILTER guard)
• components/button/button_gpio.c — pass hys_ctrl_mode into gpio_config_t (behind same guard)
• components/button/idf_component.yml — version bump 4.1.6 → 4.1.7
• components/button/CHANGELOG.md — added v4.1.7 entry

Usage on ESP32-P4:

button_gpio_config_t gpio_cfg = {
    .gpio_num      = 0,
    .active_level  = 0,
#if SOC_GPIO_SUPPORT_PIN_HYS_FILTER
    .hys_ctrl_mode = GPIO_HYS_SOFT_ENABLE,
#endif
};

Existing code that does not set the field continues to work unchanged (calloc zero-initialises the struct, which maps to hysteresis disabled).

Related

Fixes #663

Testing

• Compiled for esp32p4 target: gpio_conf.hys_ctrl_mode is picked up correctly, no warnings.
• Compiled for esp32s3 / esp32c3 targets: #if SOC_GPIO_SUPPORT_PIN_HYS_FILTER evaluates to false, struct and .c code compile unchanged — no regressions.
• Manual test on ESP32-P4 EVB: GPIO with a slow-rising edge (RC ~ 10 ms) previously produced 5–10 spurious events per press; with GPIO_HYS_SOFT_ENABLE exactly one BUTTON_PRESS_DOWN and one BUTTON_PRESS_UP event are received.

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Checklist

• 🚨 This PR does not introduce breaking changes.
• All CI checks (GH Actions) pass.
• Documentation is updated as needed.
• Tests are updated or added as necessary.
• Code is well-commented, especially in complex areas.
• Git history is clean — commits are squashed to the minimum necessary.

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Note on Tests: The existing test_apps/ GPIO button tests compile and pass unchanged. A dedicated unit test for the hysteresis path would require hardware (ESP32-P4) and a controlled slow-edge signal source, which is beyond the scope of a CI-only check — the manual test result is described above.

[CLAassistant]

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