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/exploiting-api-injection-vulnerabilities/SKILL.md

@@ -1,14 +1,12 @@
 ---
 name: exploiting-api-injection-vulnerabilities
-description: 'Tests APIs for injection vulnerabilities including SQL injection, NoSQL
-  injection, OS command injection, LDAP injection, and Server-Side Request Forgery
-  (SSRF) through API parameters, headers, and request bodies. The tester crafts malicious
-  payloads targeting different backend technologies and injection contexts to extract
-  data, execute commands, or access internal services. Maps to OWASP API8:2023 Security
-  Misconfiguration and API7:2023 SSRF. Activates for requests involving API injection
-  testing, SQLi in APIs, NoSQL injection, SSRF testing, or API input validation assessment.
-
-  '
+description: >-
+  Tests API parameters, headers, and request bodies for injection flaws — SQL injection,
+  NoSQL injection, OS command injection, LDAP injection, and SSRF — by crafting
+  payloads tailored to the target backend to extract data, execute commands, or
+  reach internal services, mapped to OWASP API8:2023 and API7:2023 SSRF. Use when
+  performing SQLi, NoSQL injection, command injection, or SSRF testing against APIs,
+  or assessing API input validation.
 domain: cybersecurity
 subdomain: api-security
 tags: