fix: missing index.md from doc folder

.gitignore

@@ -16,7 +16,6 @@ dockerout.txt
 AGENTS.md
 lessons_learnt.md
 *.log
-/doc/*.md
 wasuro
 src/core/core.version.pas
 site/*

doc/index.md

@@ -0,0 +1,32 @@
+# Asuro OS
+
+Asuro is a 32-bit x86 operating system kernel written in Free Pascal and x86 assembly.
+
+## Documentation Structure
+
+- **Kernel Entry** -- The `asuro.pas` main unit and boot sequence.
+- **Architecture (x86)** -- CPU initialization, descriptor tables, interrupt handling, fault handlers, memory management, and process scheduling for the i386 target.
+- **Boot** -- Splash screen and early boot visuals.
+- **Core** -- Foundational libraries including data structures, encoding algorithms, string handling, graphics primitives, and the kernel panic subsystem.
+- **Memory** -- Heap allocator (`kalloc`/`kfree`) and page-level allocation.
+- **Processes** -- Process lifecycle, round-robin scheduling, and inter-process messaging.
+- **I/O** -- Standard I/O (shell command dispatch) and the system log fan-out.
+- **Debug** -- Execution tracer with ring-buffer call stack recording.
+- **Drivers** -- Hardware abstraction covering PCI/USB buses, HID devices, networking (E1000, TCP/IP stack), storage (IDE, AHCI, VFS, file systems), video (VESA, LVGL, double-buffering), serial I/O, and timers.
+- **Services** -- Background daemons for graphics rendering and USB hotplug.
+- **Applications** -- Userland commands and utilities: terminal, text editor, disk tools, network tools, and a WebAssembly runtime.
+- **Compatibility** -- Shim layers for legacy code.
+- **LVGL Headers** -- Configuration and patches for the LVGL v9.2.2 GUI library.
+- **Planning** -- Design documents and architectural notes for subsystems under development.
+- **Toolchain** -- Build pipeline documentation covering compilation, linking, and ISO generation.
+
+## Building
+
+The kernel is built inside Docker using a containerized FreePascal 3.2.2 toolchain:
+
+```bash
+docker compose build builder
+docker compose run builder
+```
+
+The documentation site will be available at `http://docs.asuro.xyz`.