Add editable Samba global configuration with net conf setparm

Backend:
- Use 'net conf setparm' to update individual parameters
- Accept dictionary of key-value pairs in API

Frontend:
- Add Edit/Cancel/Save buttons to Samba Config tab
- Inline editing of configuration values
- Save changes back to registry

Changes are applied immediately via net conf setparm.

Co-Authored-By: Patrick <patrick@perlbach24.de>

backend/services/shares.py

@@ -216,42 +216,21 @@ class SharesManager:
             logger.error(f"Error reading Samba registry config: {e}")
             return {"parameters": []}
 
-    def set_samba_global_config(self, config_text: str) -> bool:
-        """Write Samba global configuration section"""
-        if not SAMBA_CONFIG.exists():
-            return False
-
+    def set_samba_global_config(self, parameters: Dict[str, str]) -> bool:
+        """Update Samba global configuration parameters using 'net conf setparm'"""
         try:
-            with open(SAMBA_CONFIG, 'r') as f:
-                lines = f.readlines()
+            for key, value in parameters.items():
+                result = subprocess.run(
+                    ['/usr/bin/net', 'conf', 'setparm', 'global', key, value],
+                    capture_output=True,
+                    text=True,
+                    timeout=10
+                )
+                if result.returncode != 0:
+                    logger.error(f"Failed to set {key}={value}: {result.stderr}")
+                    return False
 
-            # Find global section and shares
-            output_lines = []
-            skip_global = False
-            for i, line in enumerate(lines):
-                if line.strip().startswith('[global]'):
-                    skip_global = True
-                    output_lines.append('[global]\n')
-                    # Add config lines
-                    for config_line in config_text.split('\n'):
-                        if config_line.strip():
-                            output_lines.append('    ' + config_line + '\n')
-                    output_lines.append('\n')
-                    continue
-
-                if skip_global:
-                    if line.strip().startswith('['):
-                        skip_global = False
-                        output_lines.append(line)
-                    continue
-
-                output_lines.append(line)
-
-            with open(SAMBA_CONFIG, 'w') as f:
-                f.writelines(output_lines)
-
-            subprocess.run(['smbcontrol', 'smbd', 'reload-config'], capture_output=True, timeout=10)
-            logger.info("Samba global config updated")
+            logger.info(f"Samba global config updated: {len(parameters)} parameters")
             return True
         except Exception as e:
             logger.error(f"Error writing Samba global config: {e}")