Initial lookbook implementation

Pinterest-style visual bookmarking app with:
- URL metadata extraction (OG/Twitter meta, oEmbed fallback)
- Image caching in Postgres with 480px thumbnails
- Multi-tag filtering with Ctrl/Cmd for OR mode
- Fuzzy tag suggestions and inline tag editing
- Browser console auth() with first-use password setup
- Brutalist UI with Commit Mono font and Pico CSS
- Light/dark mode via browser preference

vendor/github.com/jackc/pgx/v5/internal/pgio/README.md

@@ -0,0 +1,6 @@
+# pgio
+
+Package pgio is a low-level toolkit building messages in the PostgreSQL wire protocol.
+
+pgio provides functions for appending integers to a []byte while doing byte
+order conversion.

vendor/github.com/jackc/pgx/v5/internal/pgio/doc.go

@@ -0,0 +1,6 @@
+// Package pgio is a low-level toolkit building messages in the PostgreSQL wire protocol.
+/*
+pgio provides functions for appending integers to a []byte while doing byte
+order conversion.
+*/
+package pgio

vendor/github.com/jackc/pgx/v5/internal/pgio/write.go

@@ -0,0 +1,40 @@
+package pgio
+
+import "encoding/binary"
+
+func AppendUint16(buf []byte, n uint16) []byte {
+	wp := len(buf)
+	buf = append(buf, 0, 0)
+	binary.BigEndian.PutUint16(buf[wp:], n)
+	return buf
+}
+
+func AppendUint32(buf []byte, n uint32) []byte {
+	wp := len(buf)
+	buf = append(buf, 0, 0, 0, 0)
+	binary.BigEndian.PutUint32(buf[wp:], n)
+	return buf
+}
+
+func AppendUint64(buf []byte, n uint64) []byte {
+	wp := len(buf)
+	buf = append(buf, 0, 0, 0, 0, 0, 0, 0, 0)
+	binary.BigEndian.PutUint64(buf[wp:], n)
+	return buf
+}
+
+func AppendInt16(buf []byte, n int16) []byte {
+	return AppendUint16(buf, uint16(n))
+}
+
+func AppendInt32(buf []byte, n int32) []byte {
+	return AppendUint32(buf, uint32(n))
+}
+
+func AppendInt64(buf []byte, n int64) []byte {
+	return AppendUint64(buf, uint64(n))
+}
+
+func SetInt32(buf []byte, n int32) {
+	binary.BigEndian.PutUint32(buf, uint32(n))
+}