Initial commit: xenia-rs workspace for Xbox 360 RE

Rust reimplementation of the xenia Xbox 360 emulator targeting reverse-
engineering and preservation, initially scoped to Project Sylpheed.

Includes:
- XEX2 loader (LZX decompression, AES decryption, PE parsing)
- XISO / XGD2 disc image VFS
- PPC interpreter with 200+ opcodes and VMX128 decoding
- Static analyzer: functions, cross-references, labels, asm + SQLite output
- HLE kernel covering the xboxkrnl/xam subset used by Sylpheed init
- Debugger with in-memory and SQLite-backed execution tracing
- `xenia-rs` CLI with extract/dis/exec commands that produce cumulative,
  superset SQLite databases and opt-in instruction/import/branch traces

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

crates/xenia-xex/src/header.rs

@@ -0,0 +1,128 @@
+use serde::Serialize;
+
+/// XEX2 file header. Parsed from the beginning of an Xbox 360 executable.
+#[derive(Debug, Serialize)]
+pub struct Xex2Header {
+    pub magic: u32,
+    pub module_flags: u32,
+    pub header_size: u32,
+    pub security_offset: u32,
+    pub header_count: u32,
+    pub optional_headers: Vec<Xex2OptionalHeader>,
+    pub security_info: Option<Xex2SecurityInfo>,
+    /// Parsed file format info (if present).
+    pub file_format_info: Option<FileFormatInfo>,
+    /// Parsed import libraries (addresses only until resolve_imports is called).
+    pub import_libraries: Vec<ImportLibrary>,
+    /// Execution info (title ID, media ID, etc.).
+    pub execution_info: Option<ExecutionInfo>,
+    /// Original PE name from the XEX header.
+    pub original_pe_name: Option<String>,
+}
+
+#[derive(Debug, Serialize)]
+pub struct Xex2OptionalHeader {
+    pub key: u32,
+    pub value: u32,
+}
+
+#[derive(Debug, Serialize)]
+pub struct Xex2SecurityInfo {
+    pub image_size: u32,
+    pub load_address: u32,
+    pub export_table_address: u32,
+    pub image_flags: u32,
+    /// Encrypted session key (decrypted with retail/devkit key to get actual session key).
+    pub aes_key: [u8; 16],
+    pub page_descriptors: Vec<Xex2PageDescriptor>,
+}
+
+#[derive(Debug, Clone, Copy, Serialize)]
+pub struct Xex2PageDescriptor {
+    pub size_and_info: u32,
+}
+
+impl Xex2PageDescriptor {
+    pub fn page_count(&self) -> u32 {
+        self.size_and_info >> 4
+    }
+
+    pub fn info(&self) -> u32 {
+        self.size_and_info & 0xF
+    }
+}
+
+/// File format info (compression and encryption types).
+#[derive(Debug, Clone, Serialize)]
+pub struct FileFormatInfo {
+    pub info_size: u32,
+    pub encryption_type: u16,
+    pub compression_type: u16,
+    /// For basic compression: list of (data_size, zero_size) block pairs.
+    pub basic_blocks: Vec<BasicCompressionBlock>,
+    /// For normal (LZX) compression: window size.
+    pub normal_window_size: u32,
+    /// For normal (LZX) compression: first block size (from header).
+    pub normal_first_block_size: u32,
+    /// For normal (LZX) compression: first block hash (from header).
+    pub normal_first_block_hash: [u8; 20],
+}
+
+#[derive(Debug, Clone, Copy, Serialize)]
+pub struct BasicCompressionBlock {
+    pub data_size: u32,
+    pub zero_size: u32,
+}
+
+/// An imported library with its resolved imports.
+#[derive(Debug, Clone, Serialize)]
+pub struct ImportLibrary {
+    pub name: String,
+    pub id: u32,
+    pub version_min: u32,
+    pub version_cur: u32,
+    /// Import entries. Before `resolve_imports`, these contain addresses but no ordinals.
+    /// After `resolve_imports`, ordinals and record types are filled in from the PE image.
+    pub imports: Vec<ImportEntry>,
+}
+
+/// A single import entry within an import library.
+#[derive(Debug, Clone, Serialize)]
+pub struct ImportEntry {
+    pub ordinal: u16,
+    pub record_type: u8, // 0 = variable, 1 = thunk
+    pub address: u32,
+}
+
+/// Execution info parsed from the XEX header.
+#[derive(Debug, Clone, Serialize)]
+pub struct ExecutionInfo {
+    pub media_id: u32,
+    pub title_id: u32,
+    pub disc_number: u8,
+    pub disc_count: u8,
+}
+
+/// XEX2 magic: "XEX2"
+pub const XEX2_MAGIC: u32 = 0x58455832;
+
+/// Compression types
+pub const COMPRESSION_NONE: u16 = 0;
+pub const COMPRESSION_BASIC: u16 = 1;
+pub const COMPRESSION_NORMAL: u16 = 2;
+
+/// Encryption types
+pub const ENCRYPTION_NONE: u16 = 0;
+pub const ENCRYPTION_NORMAL: u16 = 1;
+
+/// Optional header keys
+pub mod header_keys {
+    pub const ENTRY_POINT: u32 = 0x00010100;
+    pub const IMAGE_BASE_ADDRESS: u32 = 0x00010201;
+    pub const IMPORT_LIBRARIES: u32 = 0x000103FF;
+    pub const TLS_INFO: u32 = 0x00020200;
+    pub const EXECUTION_INFO: u32 = 0x00040006;
+    pub const DEFAULT_STACK_SIZE: u32 = 0x00020104;
+    pub const ORIGINAL_PE_NAME: u32 = 0x000183FF;
+    pub const FILE_FORMAT_INFO: u32 = 0x000003FF;
+}