Replace Vite/React scaffold with Go build spec

- AGENTS.md: build spec for Paperclip (constraints, conventions, 7 phases)
- docs/phase-1..7: per-phase work, DoD, out-of-scope, risks
- reference/: frozen decisions, stack+ports+budgets, content map, acceptance tests
- agents/: persona and security policy drafts
- Retires the React scaffold; history retained as record of the false start

.gitignore

@@ -1,24 +1,20 @@
-# Logs
-logs
+# build output
+/dist/
+/current/
+*.test
+*.out
+
+# generated templ files
+*_templ.go
+
+# local
+.env
+.env.*
+!.env.example
 *.log
-npm-debug.log*
-yarn-debug.log*
-yarn-error.log*
-pnpm-debug.log*
-lerna-debug.log*
+node_modules/
+.venv/
 
-node_modules
-dist
-dist-ssr
-*.local
-
-# Editor directories and files
-.vscode/*
-!.vscode/extensions.json
-.idea
-.DS_Store
-*.suo
-*.ntvs*
-*.njsproj
-*.sln
-*.sw?
+# data
+/data/
+/qdrant_storage/