fix: Fix product page syntax errors

1. Remove duplicate/broken code in product tables section
2. Fix PostCSS config for Tailwind 4
3. Add @tailwindcss/postcss dependency
4. Remove --production flag from Dockerfile (sharp required)

All fixes enable successful Docker build with favicon working.

node_modules/mdast-util-gfm-table/index.d.ts

@@ -0,0 +1,54 @@
+export type {Options} from './lib/index.js'
+
+export {gfmTableFromMarkdown, gfmTableToMarkdown} from './lib/index.js'
+
+// Add custom data tracked to turn markdown into a tree.
+declare module 'mdast-util-from-markdown' {
+  interface CompileData {
+    /**
+     * Whether we’re currently in a table.
+     */
+    inTable?: boolean | undefined
+  }
+}
+
+// Add custom data tracked to turn a syntax tree into markdown.
+declare module 'mdast-util-to-markdown' {
+  interface ConstructNameMap {
+    /**
+     * Whole table.
+     *
+     * ```markdown
+     * > | | a |
+     *     ^^^^^
+     * > | | - |
+     *     ^^^^^
+     * ```
+     */
+    table: 'table'
+
+    /**
+     * Table cell.
+     *
+     * ```markdown
+     * > | | a |
+     *     ^^^^^
+     *   | | - |
+     * ```
+     */
+    tableCell: 'tableCell'
+
+    /**
+     * Table row.
+     *
+     * ```markdown
+     * > | | a |
+     *     ^^^^^
+     *   | | - |
+     * ```
+     */
+    tableRow: 'tableRow'
+  }
+}
+
+// Note: `Table` is exposed from `@types/mdast`.