v1.2.0 — Linux Flasher, Kali Creator, fixed flashing & counterfeit detection

New features:
- Linux Flasher tab: download+decompress+flash pipeline for RPi OS, Ubuntu,
  Debian, Fedora, Kali, DietPi, Alpine, Arch ARM with built-in image catalog
- Kali Creator tab: 4 sub-tabs for USB/SD, VM creation, Docker/Podman
  container pulls, and cloud image downloads
- DownloadManager: async downloads with resume support and speed tracking
- Decompressor: streaming .xz (xz-embedded), .gz (zlib), .zip decompression
- ImageCatalog: built-in catalog + remote fetch from rpi-imager JSON endpoint
- SevenZipExtractor: QProcess wrapper for 7z.exe with progress parsing
- Bundled xz-embedded third-party library for native XZ decompression

Bug fixes:
- Fixed VirtualDisk::flashToDisk() — added FSCTL_ALLOW_EXTENDED_DASD_IO,
  FSCTL_LOCK_VOLUME, FSCTL_DISMOUNT_VOLUME, 32MB aligned buffers,
  WriteFile retry logic (3 attempts), FlushFileBuffers before close
- Fixed VirtualDisk::captureFromDisk() with same improvements
- Fixed ImagingTab::onFlashIso() — now populates targetVolumeLetters from
  disk snapshot so IsoFlasher can properly lock/dismount volumes
- Fixed SD card counterfeit detection false positives:
  - Changed from write-one-read-one to write-all-then-read-all algorithm
    to properly detect NAND address wrapping on fake cards
  - Added volume lock/dismount before probing to prevent filesystem
    interference (journal writes, metadata updates)
  - Added FSCTL_ALLOW_EXTENDED_DASD_IO for probes near end of disk
  - Fixed overly aggressive vendor string check — USB card readers
    legitimately report "USB"/"Mass Storage", no longer flagged
  - Added handle re-open between write and verify phases to defeat
    USB reader hardware cache
- README: documented how to unlock the secret menu, added new feature docs

third_party/xz-embedded/xz_lzma2.h

@@ -0,0 +1,116 @@
+/*
+ * LZMA2 decoder - Internal constants and structures
+ *
+ * Based on xz-embedded by Lasse Collin (public domain).
+ */
+
+#ifndef XZ_LZMA2_H
+#define XZ_LZMA2_H
+
+#include "xz_private.h"
+
+/* Range coder constants */
+#define RC_SHIFT_BITS       8
+#define RC_TOP_BITS         24
+#define RC_TOP_VALUE        (1U << RC_TOP_BITS)
+#define RC_BIT_MODEL_TOTAL_BITS 11
+#define RC_BIT_MODEL_TOTAL  (1 << RC_BIT_MODEL_TOTAL_BITS)
+#define RC_MOVE_BITS        5
+
+/*
+ * Maximum number of position bits (lp + pb combined).
+ * LZMA uses up to 4 position bits.
+ */
+#define POS_STATES_MAX      (1 << 4)
+
+/*
+ * The LZMA state machine has 12 states. States 0-6 indicate that the
+ * previous output was a literal; states 7-11 indicate a match/rep.
+ */
+#define STATES              12
+
+/* Special state values */
+#define LIT_STATES          7
+
+/* Match length constants */
+#define MATCH_LEN_MIN       2
+#define LEN_LOW_BITS        3
+#define LEN_LOW_SYMBOLS     (1 << LEN_LOW_BITS)
+#define LEN_MID_BITS        3
+#define LEN_MID_SYMBOLS     (1 << LEN_MID_BITS)
+#define LEN_HIGH_BITS       8
+#define LEN_HIGH_SYMBOLS    (1 << LEN_HIGH_BITS)
+
+/* Total number of match length probabilities */
+#define LEN_SYMBOLS         (LEN_LOW_SYMBOLS + LEN_MID_SYMBOLS + LEN_HIGH_SYMBOLS)
+
+/* Distance slots */
+#define DIST_STATES         4
+#define DIST_SLOT_BITS      6
+#define DIST_SLOTS          (1 << DIST_SLOT_BITS)
+#define DIST_MODEL_START    4
+#define DIST_MODEL_END      14
+#define FULL_DISTANCES      (1 << (DIST_MODEL_END / 2))
+
+/* Alignment bits for distance decoding */
+#define ALIGN_BITS          4
+#define ALIGN_SIZE          (1 << ALIGN_BITS)
+#define ALIGN_MASK          (ALIGN_SIZE - 1)
+
+/* Total number of LZMA probability variables */
+#define PROBS_SIZE_LIT(lc)  (3U << (lc))
+
+/* Literal coder */
+#define LITERAL_CODERS_MAX  (1 << 4)   /* max lc = 4 */
+
+/* LZMA2 control byte values */
+#define LZMA2_CONTROL_LZMA          0x80
+#define LZMA2_CONTROL_COPY_NO_RESET 0x01
+#define LZMA2_CONTROL_COPY_RESET    0x02
+
+/*
+ * lzma_state_is_literal: Returns true if the given LZMA state indicates
+ * that the previous symbol was a literal.
+ */
+static inline int lzma_state_is_literal(uint32_t state)
+{
+    return state < LIT_STATES;
+}
+
+/*
+ * State transitions after different symbol types.
+ */
+static inline uint32_t lzma_state_literal(uint32_t state)
+{
+    if (state <= 3)
+        return 0;
+    if (state <= 9)
+        return state - 3;
+    return state - 6;
+}
+
+static inline uint32_t lzma_state_match(uint32_t state)
+{
+    return state < LIT_STATES ? 7 : 10;
+}
+
+static inline uint32_t lzma_state_long_rep(uint32_t state)
+{
+    return state < LIT_STATES ? 8 : 11;
+}
+
+static inline uint32_t lzma_state_short_rep(uint32_t state)
+{
+    return state < LIT_STATES ? 9 : 11;
+}
+
+/*
+ * Get the distance state (0..3) from the match length.
+ */
+static inline uint32_t lzma_get_dist_state(uint32_t len)
+{
+    return len < DIST_STATES + MATCH_LEN_MIN
+        ? len - MATCH_LEN_MIN : DIST_STATES - 1;
+}
+
+#endif /* XZ_LZMA2_H */