fix: major build system improvements and container output issues

- Fix container output visibility with proper TTY handling and debug mode
- Fix build order: kernel modules built before initramfs creation
- Implement two-stage kernel build to resolve chicken-and-egg dependency
- Fix sed command issues in kernel configuration with direct execution
- Add diffutils package to container for proper kernel build support
- Enhance NIC module/firmware correlation with intelligent selection
- Fix module staging logic: all NICs loaded in stage1 before network up
- Add smart firmware installation based on module requirements
- Create comprehensive function documentation (scripts/functionlist.md)
- Add debug container script for troubleshooting

Major fixes:
* Container builds now show real-time output
* Kernel builds work with proper GNU diff support
* Module/firmware selection optimized for common hardware
* Build process handles dependencies correctly
* Documentation provides complete function reference

scripts/lib/common.sh

@@ -55,8 +55,8 @@ function safe_execute() {
     local cmd="$*"
     log_info "Executing: ${cmd}"
     
-    if [[ "${DEBUG:-0}" == "1" ]]; then
-        # In debug mode, show all output
+    if [[ "${DEBUG:-0}" == "1" ]] || in_container; then
+        # In debug mode or container, show all output for visibility
         if ! ${cmd}; then
             log_error "Command failed: ${cmd}"
             exit 1
@@ -68,6 +68,9 @@ function safe_execute() {
             log_error "Command failed: ${cmd}"
             log_error "Output: ${output}"
             exit 1
+        else
+            # Show minimal progress indicator for non-debug mode
+            log_debug "Command completed successfully: ${cmd}"
         fi
     fi
 }