fix(skills): move platforms key out of folded description: > scalars

The platforms-frontmatter sweep inserted 'platforms: [linux, macos, windows]'
immediately after 'description: >' on 5 optional-skills, landing inside the
folded scalar and breaking YAML parsing. docs-site-checks tripped on
one-three-one-rule/SKILL.md and would have failed on the other 4 in turn.

Fixed files:
- optional-skills/communication/one-three-one-rule/SKILL.md
- optional-skills/health/fitness-nutrition/SKILL.md
- optional-skills/health/neuroskill-bci/SKILL.md
- optional-skills/research/drug-discovery/SKILL.md
- optional-skills/security/oss-forensics/SKILL.md

Moved each platforms line below the closing of the description block.
All 161 SKILL.md files across the repo now parse as valid YAML.

optional-skills/health/fitness-nutrition/SKILL.md

@@ -1,12 +1,12 @@
 ---
 name: fitness-nutrition
 description: >
-platforms: [linux, macos, windows]
   Gym workout planner and nutrition tracker. Search 690+ exercises by muscle,
   equipment, or category via wger. Look up macros and calories for 380,000+
   foods via USDA FoodData Central. Compute BMI, TDEE, one-rep max, macro
   splits, and body fat — pure Python, no pip installs. Built for anyone
   chasing gains, cutting weight, or just trying to eat better.
+platforms: [linux, macos, windows]
 version: 1.0.0
 authors:
   - haileymarshall

optional-skills/health/neuroskill-bci/SKILL.md

@@ -1,12 +1,12 @@
 ---
 name: neuroskill-bci
 description: >
-platforms: [linux, macos, windows]
   Connect to a running NeuroSkill instance and incorporate the user's real-time
   cognitive and emotional state (focus, relaxation, mood, cognitive load, drowsiness,
   heart rate, HRV, sleep staging, and 40+ derived EXG scores) into responses.
   Requires a BCI wearable (Muse 2/S or OpenBCI) and the NeuroSkill desktop app
   running locally.
+platforms: [linux, macos, windows]
 version: 1.0.0
 author: Hermes Agent + Nous Research
 license: MIT