init: scaffold Seth-Workflow-April-2026

User-agnostic, shareable AI-assisted development workflow distilled from
26+ real projects. Includes 9 composable rules, 4 project templates,
pre-push secret scanning hook, 3 methodology guides, and customization docs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

templates/IDEA.md

@@ -0,0 +1,20 @@
+# IDEA.md -- Project Idea
+
+> This is the starting point an AI agent reads before any code exists.
+> Keep it honest and rough -- it does not need to be polished.
+
+## What is this?
+
+<Describe the project in plain language. What does it do? Who is it for?>
+
+## Problem it solves
+
+<What pain point or gap does this address? Why does it need to exist?>
+
+## Constraints / preferences
+
+<Language, stack, deployment target, performance requirements, anything relevant.>
+
+## Success criteria
+
+<How do you know this is done? What does "working" look like?>