fix: add finance/ to scripts, CI, README, and CONTRIBUTING.md (#437)

Adds finance/ to AGENT_DIRS in all 3 scripts, CI workflow trigger paths, CONTRIBUTING.md category list, and README.md division roster. Also fixes duplicate sales entry in lint-agents.sh.

.github/workflows/lint-agents.yml

@@ -6,6 +6,7 @@ on:
       - "academic/**"
       - "design/**"
       - "engineering/**"
+      - "finance/**"
       - "game-development/**"
       - "marketing/**"
       - "paid-media/**"
@@ -30,7 +31,7 @@ jobs:
         id: changed
         run: |
           FILES=$(git diff --name-only --diff-filter=ACMR origin/${{ github.base_ref }}...HEAD -- \
-            'academic/**/*.md' 'design/**/*.md' 'engineering/**/*.md' 'game-development/**/*.md' 'marketing/**/*.md' 'paid-media/**/*.md' 'sales/**/*.md' 'product/**/*.md' \
+            'academic/**/*.md' 'design/**/*.md' 'engineering/**/*.md' 'finance/**/*.md' 'game-development/**/*.md' 'marketing/**/*.md' 'paid-media/**/*.md' 'sales/**/*.md' 'product/**/*.md' \
             'project-management/**/*.md' 'testing/**/*.md' 'support/**/*.md' \
             'spatial-computing/**/*.md' 'specialized/**/*.md')
           {