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.

07_dos/README.md

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+[← Home](../README.md)
+
+# dos.library — AmigaDOS Overview
+
+## Section Index
+
+| File | Description |
+|---|---|
+| [dos_base.md](dos_base.md) | DosLibrary structure and global state |
+| [file_io.md](file_io.md) | Open, Close, Read, Write, Seek |
+| [locks_examine.md](locks_examine.md) | Lock, UnLock, Examine, ExNext, ExAll |
+| [pattern_matching.md](pattern_matching.md) | ParsePattern, MatchPattern, wildcards |
+| [process_management.md](process_management.md) | CreateNewProc, SystemTagList, Execute |
+| [packet_system.md](packet_system.md) | DosPacket, ACTION_* codes, handler protocol |
+| [filesystem.md](filesystem.md) | FFS/OFS layout, block structure |
+| [environment.md](environment.md) | GetVar/SetVar, local/global env variables |
+| [error_handling.md](error_handling.md) | IoErr, Fault, PrintFault, error codes |
+| [cli_shell.md](cli_shell.md) | CLI/Shell: pipes, redirection, scripts, ReadArgs |