refactor: convert to bun-workspaces monorepo (desktop/ + www/)

- Move the Tauri app (React frontend + Rust backend) into desktop/ via
  git mv — configs unchanged (relative paths: tauri.conf.json, vite.config.ts)
- Root package.json becomes a private bun workspace container with
  orchestration scripts; desktop package renamed gridline-desktop
- Scaffold www/ with Astro 7 + Tailwind v4 (hand-wired vite plugin,
  static output, ready for Dokploy)
- Update release.yml for the new layout: projectPath: desktop,
  desktop/src-tauri resource paths, rust-cache workspace path
- Update README + AGENTS.md structure trees and dev commands
- Verified: vitest (1074), cargo test (354), desktop build, tauri dev
  (window launches), tauri build (dmg + app bundles), Astro build

desktop/src/lib/dbIcons.tsx

@@ -0,0 +1,97 @@
+import { siPostgresql, siMysql, siSqlite, siRedis, siSupabase, siNeon } from "simple-icons";
+import type { DbType } from "./types";
+
+// Brand colors from simple-icons
+const DB_COLORS: Record<DbType, string> = {
+  postgresql: `#${siPostgresql.hex}`,
+  mysql: `#${siMysql.hex}`,
+  redis: `#${siRedis.hex}`,
+  sqlite: `#${siSqlite.hex}`,
+};
+
+// SVG path data for each DB icon
+const DB_PATHS: Record<DbType, string> = {
+  postgresql: siPostgresql.path,
+  mysql: siMysql.path,
+  redis: siRedis.path,
+  sqlite: siSqlite.path,
+};
+
+export const DB_LABELS: Record<DbType, string> = {
+  postgresql: "PostgreSQL",
+  mysql: "MySQL",
+  redis: "Redis",
+  sqlite: "SQLite",
+};
+
+interface DbIconProps {
+  type: DbType;
+  size?: number;
+  className?: string;
+}
+
+export function DbIcon({ type, size = 20, className }: DbIconProps) {
+  const path = DB_PATHS[type];
+  const color = DB_COLORS[type];
+  if (!path) return <span className="text-lg">❓</span>;
+
+  return (
+    <svg
+      role="img"
+      viewBox="0 0 24 24"
+      width={size}
+      height={size}
+      className={className}
+      fill={color}
+      xmlns="http://www.w3.org/2000/svg"
+    >
+      <path d={path} />
+    </svg>
+  );
+}
+
+// Keep backward compat for any legacy emoji usage
+export const DB_ICONS: Record<DbType, string> = {
+  postgresql: "🐘",
+  mysql: "🐬",
+  redis: "⚡",
+  sqlite: "🗄️",
+};
+
+// ── Managed-PostgreSQL provider icons (Supabase, NeonDB) ──────────
+// These are NOT DbType values; connections persist as db_type="postgresql".
+type ProviderIconId = "supabase" | "neon";
+
+const PROVIDER_ICON_DATA: Record<ProviderIconId, { hex: string; path: string }> = {
+  supabase: { hex: `#${siSupabase.hex}`, path: siSupabase.path },
+  neon: { hex: `#${siNeon.hex}`, path: siNeon.path },
+};
+
+export const PROVIDER_LABELS: Record<ProviderIconId, string> = {
+  supabase: "Supabase",
+  neon: "NeonDB",
+};
+
+interface ProviderIconProps {
+  id: ProviderIconId;
+  size?: number;
+  className?: string;
+}
+
+export function ProviderIcon({ id, size = 20, className }: ProviderIconProps) {
+  const data = PROVIDER_ICON_DATA[id];
+  if (!data) return <span className="text-lg">❓</span>;
+  return (
+    <svg
+      role="img"
+      viewBox="0 0 24 24"
+      width={size}
+      height={size}
+      className={className}
+      fill={data.hex}
+      xmlns="http://www.w3.org/2000/svg"
+    >
+      <path d={data.path} />
+    </svg>
+  );
+}