Map all 754 skills to MITRE ATT&CK v19.1

- Add validated mitre_attack frontmatter to all 754 skills (286 distinct
  techniques), verified against MITRE ATT&CK v19.1 via the official
  mitreattack-python library: 0 revoked, deprecated, or invalid IDs
- Curate precise per-skill technique IDs for forensics, malware-analysis,
  threat-intel, and red-team skills (e.g. DCSync -> T1003.006,
  Kerberoasting -> T1558.003, Pass-the-Ticket -> T1550.003)
- Reconcile v19.1 tactic restructuring: Defense Evasion split into
  Stealth (TA0005) and Defense Impairment (TA0112); revoked T1562.*
  family and T1070.001/.002 remapped to active equivalents (T1685.*)
- Normalize word-split tags across 35 skills (remove filename-derived
  stopword tags, add semantic cybersecurity tags)
- Add api-reference.md for 3 skills that were missing it
- Update README ATT&CK section with accurate v19.1 tactic distribution

skills/reverse-engineering-android-malware-with-jadx/SKILL.md

@@ -1,9 +1,11 @@
 ---
 name: reverse-engineering-android-malware-with-jadx
-description: 'Reverse engineers malicious Android APK files using JADX decompiler to analyze Java/Kotlin source code, identify
-  malicious functionality including data theft, C2 communication, privilege escalation, and overlay attacks. Examines manifest
-  permissions, receivers, services, and native libraries. Activates for requests involving Android malware analysis, APK reverse
-  engineering, mobile malware investigation, or Android threat analysis.
+description: 'Reverse engineers malicious Android APK files using JADX decompiler
+  to analyze Java/Kotlin source code, identify malicious functionality including data
+  theft, C2 communication, privilege escalation, and overlay attacks. Examines manifest
+  permissions, receivers, services, and native libraries. Activates for requests involving
+  Android malware analysis, APK reverse engineering, mobile malware investigation,
+  or Android threat analysis.
 
   '
 domain: cybersecurity
@@ -22,6 +24,12 @@ nist_csf:
 - RS.AN-03
 - ID.RA-01
 - DE.CM-01
+mitre_attack:
+- T1027
+- T1055
+- T1140
+- T1497
+- T1068
 ---
 
 # Reverse Engineering Android Malware with JADX