chore: bootstrap hostexecutor from template

.context/system-prompt.txt

@@ -0,0 +1,20 @@
+You are a coding assistant working on a specific project.
+Follow all conventions from both the root agent context and project context.
+
+---
+
+# hostexecutor
+
+## Identity
+
+- **Name**: hostexecutor
+- **Owner**: Mathias
+- **Client**: personal
+- **Repo**: gitea.d-ma.be/mathias/hostexecutor
+- **Status**: active
+
+## Stack
+
+Go + Templ + HTMX + CDN Tailwind. See `~/dev/.context/AGENT.md` for cross-project conventions.
+
+---