feat: parse and display security info (M3)

Implement security info parsing including RSA signature, encrypted AES
key, image/region/media flags, load address, SHA-1 digests, and page
descriptors with section type classification. Add comprehensive unit
and integration tests.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/display.rs

@@ -3,6 +3,7 @@ use crate::header::Xex2Header;
 use crate::optional::{
     format_hex_bytes, format_rating, format_timestamp, HeaderKey, OptionalHeaders,
 };
+use crate::security::SecurityInfo;
 
 /// Prints the XEX2 main header in a human-readable format.
 pub fn display_header(header: &Xex2Header) {
@@ -200,3 +201,91 @@ pub fn display_optional_headers(headers: &OptionalHeaders) {
         }
     }
 }
+
+/// Prints the security info in a human-readable format.
+pub fn display_security_info(security: &SecurityInfo) {
+    println!();
+    println!("=== Security Info ===");
+    println!(
+        "Header Size:          0x{:08X} ({} bytes)",
+        security.header_size, security.header_size
+    );
+    println!(
+        "Image Size:           0x{:08X} ({} bytes)",
+        security.image_size, security.image_size
+    );
+
+    // RSA signature — show first 8 and last 8 bytes
+    let sig = &security.rsa_signature;
+    println!(
+        "RSA Signature:        {}...{} (256 bytes)",
+        sig[..4].iter().map(|b| format!("{b:02X}")).collect::<String>(),
+        sig[252..].iter().map(|b| format!("{b:02X}")).collect::<String>()
+    );
+
+    println!("Unknown (0x108):      0x{:08X}", security.unk_108);
+    println!("Image Flags:          {}", security.image_flags);
+    println!("Load Address:         0x{:08X}", security.load_address);
+    println!(
+        "Section Digest:       {}",
+        format_hex_bytes(&security.section_digest)
+    );
+    println!("Import Table Count:   {}", security.import_table_count);
+    println!(
+        "Import Table Digest:  {}",
+        format_hex_bytes(&security.import_table_digest)
+    );
+    println!(
+        "XGD2 Media ID:        {}",
+        security
+            .xgd2_media_id
+            .iter()
+            .map(|b| format!("{b:02X}"))
+            .collect::<String>()
+    );
+    println!(
+        "AES Key (encrypted):  {}",
+        format_hex_bytes(&security.aes_key)
+    );
+
+    if security.export_table == 0 {
+        println!("Export Table:         0x00000000 (none)");
+    } else {
+        println!("Export Table:         0x{:08X}", security.export_table);
+    }
+
+    println!(
+        "Header Digest:        {}",
+        format_hex_bytes(&security.header_digest)
+    );
+    println!("Region:               {}", security.region);
+    println!("Allowed Media Types:  {}", security.allowed_media_types);
+
+    // Page descriptors
+    println!();
+    let page_size = security.image_flags.page_size();
+    let page_size_label = if page_size == 0x1000 { "4KB" } else { "64KB" };
+    println!(
+        "Page Descriptors ({} entries, {} pages):",
+        security.page_descriptor_count, page_size_label
+    );
+
+    let mut address_offset: u64 = 0;
+    for (i, desc) in security.page_descriptors.iter().enumerate() {
+        let digest_preview: String = desc.data_digest[..6]
+            .iter()
+            .map(|b| format!("{b:02X}"))
+            .collect();
+        let size = desc.page_count as u64 * page_size as u64;
+        println!(
+            "  #{i:<4} {:<10} {:<4} pages  ({:>8} bytes)  offset +0x{address_offset:08X}  SHA1: {digest_preview}...",
+            desc.section_type.to_string(),
+            desc.page_count,
+            size
+        );
+        address_offset += size;
+    }
+    println!(
+        "  Total mapped size: 0x{address_offset:X} ({address_offset} bytes)"
+    );
+}