feat(ui): migrate to Tailwind (compiled) + Flowbite JS; new navbar/layout; Docker CSS build

- Add multi-stage CSS build that compiles Tailwind into app/static/tw.css
- Add Tailwind config with dark tokens (bg/nav/card) and purge globs
- Add assets/input.css (@tailwind base/components/utilities + small utilities)
- Replace Tailwind CDN + REMOVE Flowbite CSS (keep Flowbite JS only)
- New base_tailwind.html (top navbar, responsive container, {%- block scripts -%})
- Port pages to Tailwind look/feel with wider content column:
  - index: single-column form + recent results, fullscreen spinner overlay, copy-UUID
  - result: sticky jump list, Tailwind tables/badges, Suspicious Scripts/Forms sections
  - viewer: Monaco-based code viewer in Tailwind card, actions (copy/wrap/raw)
  - ssl_tls macro: rewritten with Tailwind (details/summary for raw JSON)
- Dockerfile: add css-builder stage and copy built tw.css into /app/app/static
- Remove Flowbite stylesheet to avoid overrides; Flowbite JS loaded with defer

BREAKING CHANGE:
Legacy CSS classes/components (.card, .badge, etc.) are replaced by Tailwind utilities.
All templates now expect tw.css to be served from /static.

tailwind/package.json

@@ -0,0 +1,6 @@
+{
+  "private": true,
+  "devDependencies": {
+    "tailwindcss": "^3.4.10"
+  }
+}

tailwind/tailwind.config.js

@@ -0,0 +1,16 @@
+module.exports = {
+  content: [
+    "./app/templates/**/*.html",
+    "./app/static/**/*.js",
+  ],
+  theme: {
+    extend: {
+      colors: {
+        bg:   "#0b0f14",
+        nav:  "#0f1720",
+        card: "#111826",
+      },
+    },
+  },
+  plugins: [],
+};