docs(amiga): complete AmigaOS 3.1/3.2 developer reference — 172 files across 17 sections

Comprehensive technical documentation covering:
- Hardware: OCS/ECS/AGA custom chip registers, Copper & Blitter deep dives
- Boot sequence: cold boot through startup-sequence
- Binary format: HUNK executable spec, relocation, debug info
- Linking & ABI: .fd files, LVO tables, register calling conventions
- Exec kernel: tasks, interrupts, memory, signals, semaphores
- AmigaDOS: file I/O, FFS/OFS layout, CLI/Shell scripting
- Graphics: planar bitmaps, Copper programming, HAM/EHB modes
- Intuition: screens, windows, IDCMP, BOOPSI
- Devices: trackdisk, SCSI, serial, timer, audio, keyboard
- Libraries: utility, expansion, IFFParse, locale, ARexx
- Networking: bsdsocket API, SANA-II, TCP/IP stack comparison
- Toolchain: GCC, vasm/vlink, SAS/C, NDK, debugging
- Reverse engineering: IDA/Ghidra setup, compiler fingerprints, case studies
- CPU & MMU: 68040/060 emulation libs, PMMU, cache management
- Driver development: SANA-II, Picasso96/RTG, AHI audio

All files include breadcrumb navigation. No local paths or proprietary content.

11_libraries/workbench.md

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+[← Home](../README.md) · [Libraries](README.md)
+
+# workbench.library — Workbench Integration
+
+## Overview
+
+`workbench.library` provides APIs for interacting with the Workbench desktop: AppWindows, AppIcons, AppMenuItems, and startup message handling.
+
+---
+
+## WBStartup Message
+
+When launched from Workbench, a program receives a `WBStartup` message instead of CLI arguments:
+
+```c
+struct WBStartup {
+    struct Message sm_Message;
+    struct MsgPort *sm_Process;   /* process that sent us */
+    BPTR   sm_Segment;            /* our loaded segment */
+    LONG   sm_NumArgs;            /* number of arguments */
+    char  *sm_ToolWindow;         /* tool window spec */
+    struct WBArg *sm_ArgList;     /* argument array */
+};
+
+struct WBArg {
+    BPTR   wa_Lock;    /* directory lock */
+    BYTE  *wa_Name;    /* filename */
+};
+```
+
+### Handling WBStartup
+
+```c
+struct WBStartup *wbmsg = NULL;
+if (!argc) {  /* launched from Workbench */
+    WaitPort(&((struct Process *)FindTask(NULL))->pr_MsgPort);
+    wbmsg = (struct WBStartup *)GetMsg(
+        &((struct Process *)FindTask(NULL))->pr_MsgPort);
+    /* Process wbmsg->sm_ArgList for file arguments */
+}
+/* ... do work ... */
+if (wbmsg) {
+    Forbid();
+    ReplyMsg((struct Message *)wbmsg);
+}
+```
+
+---
+
+## AppWindow / AppIcon / AppMenuItem
+
+```c
+/* Register a window to receive file drops: */
+struct AppWindow *appwin = AddAppWindow(1, 0, win, port, NULL);
+/* When user drags files to the window, receive AppMessage on port */
+
+struct AppMessage {
+    struct Message am_Message;
+    UWORD  am_Type;        /* AMTYPE_APPWINDOW, etc. */
+    ULONG  am_UserData;
+    ULONG  am_ID;
+    LONG   am_NumArgs;     /* number of files dropped */
+    struct WBArg *am_ArgList; /* array of file references */
+    /* ... */
+};
+
+RemoveAppWindow(appwin);
+```
+
+---
+
+## References
+
+- NDK39: `workbench/workbench.h`, `workbench/startup.h`