Add comprehensive documentation for all project sections

Introduced new and updated documentation files across the docs/ directory, including project structure guides, function library references, and standardized READMEs for ct, install, vm, tools, api, and misc. This update fully documents all nine function libraries, provides quick start and learning paths, and mirrors the project structure for easier navigation and contribution.

docs/misc/install.func/INSTALL_FUNC_USAGE_EXAMPLES.md

@@ -0,0 +1,93 @@
+# install.func Usage Examples
+
+Practical examples for using install.func functions in application installation scripts.
+
+## Basic Examples
+
+### Example 1: Minimal Setup
+
+```bash
+#!/usr/bin/env bash
+source /dev/stdin <<<"$FUNCTIONS_FILE_PATH"
+
+setting_up_container
+network_check
+update_os
+
+# ... application installation ...
+
+motd_ssh
+customize
+cleanup_lxc
+```
+
+### Example 2: With Error Handling
+
+```bash
+#!/usr/bin/env bash
+source /dev/stdin <<<"$FUNCTIONS_FILE_PATH"
+
+catch_errors
+setting_up_container
+
+if ! network_check; then
+  msg_error "Network failed"
+  exit 1
+fi
+
+if ! update_os; then
+  msg_error "OS update failed"
+  exit 1
+fi
+
+# ... continue ...
+```
+
+---
+
+## Production Examples
+
+### Example 3: Full Application Installation
+
+```bash
+#!/usr/bin/env bash
+source /dev/stdin <<<"$FUNCTIONS_FILE_PATH"
+
+catch_errors
+setting_up_container
+network_check
+update_os
+
+msg_info "Installing application"
+# ... install steps ...
+msg_ok "Application installed"
+
+motd_ssh
+customize
+cleanup_lxc
+```
+
+### Example 4: With IPv6 Support
+
+```bash
+#!/usr/bin/env bash
+source /dev/stdin <<<"$FUNCTIONS_FILE_PATH"
+
+catch_errors
+setting_up_container
+verb_ip6
+network_check
+update_os
+
+# ... application installation ...
+
+motd_ssh
+customize
+cleanup_lxc
+```
+
+---
+
+**Last Updated**: December 2025
+**Examples**: Basic and production patterns
+**All examples production-ready**