fix: reformat codebase and fix const-correctness for CI lint

- Reformat all C/H files to match .clang-format (LLVM style)
- Fix 26 cppcheck const-correctness warnings (constParameterPointer,
  constVariablePointer, constVariable)
- Update function declarations in headers to match const parameters

src/shared/config.h

@@ -3,15 +3,12 @@
 
 #include <stdbool.h>
 
-typedef enum {
-  TRANSPORT_TCP,
-  TRANSPORT_SSH
-} TransportType;
+typedef enum { TRANSPORT_TCP, TRANSPORT_SSH } TransportType;
 
 typedef struct Config {
-  char *version;
-  char *send_directory;
-  char *receive_root_directory;
+  char* version;
+  char* send_directory;
+  char* receive_root_directory;
   bool save_to_disk;
   bool use_multithreading;
   bool use_chunk_serialization;
@@ -25,33 +22,31 @@ typedef struct Config {
   unsigned long long chunk_size;
   int ssh_port;
   TransportType transport;
-  char *ssh_destination;
-  char **exclude_patterns;
+  char* ssh_destination;
+  char** exclude_patterns;
   int exclude_count;
-  char **include_patterns;
+  char** include_patterns;
   int include_count;
   unsigned long long max_size;
   unsigned long long min_size;
   bool use_incremental;
   bool use_tls;
-  char *tls_cert;
-  char *tls_key;
-  char *tls_ca;
+  char* tls_cert;
+  char* tls_key;
+  char* tls_ca;
 } Config;
 
 #define PROTOCOL_VERSION "1.1.0"
 #define DEFAULT_CHUNK_SIZE (10 * 1024 * 1024)
 
-Config *config_create(char *version, char *send_directory,
-                      char *receive_directory, bool save_to_disk,
-                      bool use_multithreading, bool use_chunk_serialization,
-                       bool use_compression, bool use_metadata,
-                       int compression_level, bool use_sendfile,
-                       unsigned long long chunk_size);
-void config_delete(Config *config);
-bool config_send(int file_descriptor, Config *config);
-Config *config_receive(int file_descriptor);
-bool is_remote_dest(const char *s);
-void config_parse_ssh_dest(Config *config);
+Config* config_create(char* version, char* send_directory, char* receive_directory,
+                      bool save_to_disk, bool use_multithreading, bool use_chunk_serialization,
+                      bool use_compression, bool use_metadata, int compression_level,
+                      bool use_sendfile, unsigned long long chunk_size);
+void config_delete(Config* config);
+bool config_send(int file_descriptor, Config* config);
+Config* config_receive(int file_descriptor);
+bool is_remote_dest(const char* s);
+void config_parse_ssh_dest(Config* config);
 
 #endif