Rewrite 548 skill descriptions to the activation rubric

Each rewritten description now states both what the skill does (concrete
capability, named tools/artifacts) and an explicit when-to-use trigger,
improving agent discovery/activation. Grounded in each skill's own body;
changes confined to the `description` field only (bodies and all other
frontmatter untouched). Produced by a gated audit->rewrite->recheck loop
(548 -> 0 flagged) with a sampled anti-invention check (0 ungrounded).

Schema: 817/817 pass. Framework-ID gate: 0 defects.

skills/detecting-rdp-brute-force-attacks/SKILL.md

@@ -1,8 +1,11 @@
 ---
 name: detecting-rdp-brute-force-attacks
-description: Detect RDP brute force attacks by analyzing Windows Security Event Logs
-  for failed authentication patterns (Event ID 4625), successful logons after failures
-  (Event ID 4624), NLA failures, and source IP frequency analysis.
+description: Detect RDP brute force attacks by parsing Windows Security Event Logs
+  (EVTX files, via python-evtx) for failed logon patterns (Event ID 4625, Logon
+  Type 10/3), correlating with successful logons (Event ID 4624), and analyzing
+  NLA failures and source IP frequency. Use when investigating exposed RDP endpoints,
+  building SIEM detection rules for credential guessing, or confirming whether
+  a compromised account followed a brute-force pattern.
 domain: cybersecurity
 subdomain: threat-detection
 tags: