Initial commit: prompt template manager

React + Tailwind frontend, FastAPI backend, settings.json storage.
Supports preset CRUD, live variable filling, and AI rewrite via OpenAI.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/models.py

@@ -0,0 +1,13 @@
+import re
+
+VAR_RE = re.compile(r'\{\{([a-zA-Z_][a-zA-Z0-9_]*)\}\}')
+
+
+def extract_vars(template: str) -> list[str]:
+    seen = set()
+    result = []
+    for m in VAR_RE.finditer(template):
+        if m.group(1) not in seen:
+            seen.add(m.group(1))
+            result.append(m.group(1))
+    return result