Remove old HAL components and refactored GPS-related code (#583)

- Added generic GPS/GNSS support with device detection, configuration, and persistent settings.
- Improved device and module lifecycle management.
- Added flexible filesystem locking support for displays and storage.
- Improved display-idle and keyboard backlight handling.
- Updated architecture, driver, module, testing, and licensing documentation.
- Removed old HAL device and related code.

TactilityKernel/source/filesystem/file_mutex.cpp

@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/filesystem/file_mutex.h>
+
+#include <cstring>
+#include <string>
+#include <vector>
+
+static const FileMutex no_mutex = {
+    .lock = nullptr,
+    .try_lock = nullptr,
+    .unlock = nullptr,
+};
+
+struct FileMutexEntry {
+    std::string path;
+    FileMutex mutex;
+};
+
+static std::vector<FileMutexEntry> mutex_entries;
+
+extern "C" {
+
+void file_mutex_register(const FileMutex* mutex, const char* path) {
+    // Skip if entry for path exists
+    for (auto& entry : mutex_entries) {
+        if (entry.path == path) {
+            return;
+        }
+    }
+
+    // Store a copy of the entry
+    mutex_entries.push_back({
+        .path = path,
+        .mutex = *mutex
+    });
+}
+
+void file_mutex_get(FileMutex* mutex, const char* path) {
+    std::string path_string = path;
+    for (auto& entry : mutex_entries) {
+        // Match the mount path itself, or a descendant (e.g. "/sdcard" registered, "/sdcard/config.json" requested).
+        bool is_match = path_string == entry.path ||
+            (entry.path == "/" && !path_string.empty() && path_string[0] == '/') ||
+            (path_string.rfind(entry.path, 0) == 0 && path_string[entry.path.size()] == '/');
+        if (is_match) {
+            memcpy(mutex, &entry.mutex, sizeof(FileMutex));
+            return;
+        }
+    }
+
+    *mutex = no_mutex;
+}
+
+void file_mutex_lock(const FileMutex* mutex) {
+    if (mutex->lock) {
+        mutex->lock();
+    }
+}
+
+bool file_mutex_try_lock(const FileMutex* mutex, TickType_t timeout) {
+    if (mutex->try_lock) {
+        return mutex->try_lock(timeout);
+    }
+    return true;
+}
+
+void file_mutex_unlock(const FileMutex* mutex) {
+    if (mutex->unlock) {
+        mutex->unlock();
+    }
+}
+
+}