TactilityKernel improvements (#464)

* **New Features**
  * Thread API with lifecycle, priority, affinity and state monitoring
  * Timer subsystem: one-shot/periodic timers, reset, pending callbacks, expiry queries
  * Expanded I²C: register-level ops, bulk writes, presence checks, ESP32 integration and new config properties
  * GPIO controller: pin level and options APIs
  * Error utilities: new error code, error-to-string, timeout helper and common macros
  * Device construction helpers (construct+start)

* **Tests**
  * New unit tests for thread and timer behavior

* **Documentation**
  * Expanded coding style guide (files/folders, C conventions)

Platforms/PlatformEsp32/Include/tactility/drivers/esp32_i2c.h

@@ -9,12 +9,18 @@ extern "C" {
 #endif
 
 struct Esp32I2cConfig {
+    i2c_port_t port;
     uint32_t clockFrequency;
-    struct GpioPinConfig pinSda;
-    struct GpioPinConfig pinScl;
-    const i2c_port_t port;
+    gpio_pin_t pinSda;
+    gpio_pin_t pinScl;
+    bool pinSdaPullUp;
+    bool pinSclPullUp;
 };
 
+error_t esp32_i2c_get_port(struct Device* device, i2c_port_t* port);
+void esp32_i2c_lock(struct Device* device);
+void esp32_i2c_unlock(struct Device* device);
+
 #ifdef __cplusplus
 }
 #endif

Platforms/PlatformEsp32/Include/tactility/error_esp32.h

@@ -4,4 +4,5 @@
 
 #include <tactility/error.h>
 
+/** Convert an esp_err_t to an error_t */
 error_t esp_err_to_error(esp_err_t error);