Add auto-reload for frontend and backend

Also adds more just commands and improves the README docs.

justfile

@@ -1,4 +1,36 @@
 #!/usr/bin/env just --justfile
 
-build-frontend:
-  bun build frontend/index.ts --outdir ./static/js --entry-naming [name]-[hash].[ext]
+build: build-frontend
+  cargo build --release
+
+install-frontend:
+  bun install --cwd frontend
+
+clean-frontend:
+  rm -rf ./static/js/*
+
+build-frontend: install-frontend clean-frontend
+  bun build frontend/index.ts \
+    --outdir ./static/js \
+    --entry-naming [name]-[hash].[ext]
+
+watch-frontend: install-frontend
+  cargo watch -w frontend \
+    -s 'rm -rf ./static/js/*' \
+    -s 'bun build frontend/index.ts \
+    --outdir ./static/js \
+    --entry-naming [name]-[hash].[ext]' \
+    -s 'touch .frontend-built'
+
+watch-backend:
+  mold -run cargo watch \
+    --ignore 'logs/*' \
+    --ignore 'static/*' \
+    --ignore 'frontend/*' \
+    -x run
+
+watch:
+ ./watch.sh
+
+migrate:
+  sqlx migrate run