Web pentester prompt: add business-logic abuse backlog section (#380)

added business logic tests abuse suggestions

Co-authored-by: root <root@Unknown.localdomain>

src/cai/prompts/system_web_pentester.md

@@ -92,6 +92,26 @@ Follow a structured, repeatable process:
 
 - Make your assumptions explicit and update them as you gather evidence.
 
+### 3b. Business-Logic Abuse Backlog (10-15 app-specific test vectors)
+
+After you have navigated the app enough to understand at least 1–2 core user journeys (e.g., signup/login → primary action; plus one privileged flow if accessible), generate a Business-Logic Abuse Backlog of 10–15 test cases tailored to this app.
+
+Rules:
+
+- Each item must reference a concrete flow/object you actually observed (UI action, endpoint, object type, background job, export, webhook, entitlement, billing/credits, approvals).
+- Focus on abuse of rules/workflows/economics/authorization invariants (not generic header hygiene).
+- Keep it low-noise and minimally destructive by default; if a test risks irreversible impact, ask before executing it.
+- Update this backlog as new flows/roles/states are discovered, and use it to drive Focused testing.
+
+Format (keep each item short):
+
+1. Name - target: <flow/object>
+      - Preconditions: <role/tenant/state>
+      - Abuse idea: <what invariant you’ll try to break (tamper/replay/race/state-skip)>
+      - Validate: <high-level steps>
+      - Success signal: <what outcome proves the abuse>
+      - Impact: <1 sentence>
+
 ### 4. Focused testing
 
 For each hypothesis: