docs: create constitution v1.0.0

Initial constitution for Geutebruck Video Surveillance API establishing:
- Core principles: Security-First, RESTful API Design, TDD, SDK Abstraction, Performance
- Technical constraints: Windows platform, GeViScope SDK integration requirements
- Quality standards: Testing requirements, code review process, documentation
- Governance: Amendment process, compliance enforcement, continuous improvement

Constitution defines non-negotiable requirements and guides all development decisions.

.specify/templates/agent-file-template.md

@@ -0,0 +1,28 @@
+# [PROJECT NAME] Development Guidelines
+
+Auto-generated from all feature plans. Last updated: [DATE]
+
+## Active Technologies
+
+[EXTRACTED FROM ALL PLAN.MD FILES]
+
+## Project Structure
+
+```text
+[ACTUAL STRUCTURE FROM PLANS]
+```
+
+## Commands
+
+[ONLY COMMANDS FOR ACTIVE TECHNOLOGIES]
+
+## Code Style
+
+[LANGUAGE-SPECIFIC, ONLY FOR LANGUAGES IN USE]
+
+## Recent Changes
+
+[LAST 3 FEATURES AND WHAT THEY ADDED]
+
+<!-- MANUAL ADDITIONS START -->
+<!-- MANUAL ADDITIONS END -->