refactor: replace hardcoded hex colors with theme tokens, move data/ to root

- Add --color-green-mid token (#4a7a55) to @theme for dimmer stat values
- Replace all text-[#hex]/bg-[#hex] arbitrary values with named tokens:
  text-green, text-green-light, text-green-sec, text-green-muted,
  text-green-dark, text-green-mid, text-text, bg-card, bg-bg, border-border
- Replace rgba(34,197,94,X) inline styles with bg-green/X opacity modifiers
- Convert single-prop style={{ borderColor/background }} to className
- Fix SVG stroke="#dff5e8" → stroke="currentColor"
- Use CSS variables in globals.css base styles (background-color, color)
- Move app/data/wikipedia/ → data/ (project root, not inside Next.js app dir)
- Update Dockerfile, seed.ts, scrape-wikipedia.ts paths accordingly
- Remove unused app/data/world_cup.csv

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

data/2010/worldcup.groups.json

@@ -0,0 +1,76 @@
+{
+  "groups": [
+    {
+      "name": "Group A",
+      "teams": [
+        "South Africa",
+        "Mexico",
+        "Uruguay",
+        "France"
+      ]
+    },
+    {
+      "name": "Group B",
+      "teams": [
+        "South Korea",
+        "Greece",
+        "Argentina",
+        "Nigeria"
+      ]
+    },
+    {
+      "name": "Group C",
+      "teams": [
+        "England",
+        "United States",
+        "Algeria",
+        "Slovenia"
+      ]
+    },
+    {
+      "name": "Group D",
+      "teams": [
+        "Serbia",
+        "Ghana",
+        "Germany",
+        "Australia"
+      ]
+    },
+    {
+      "name": "Group E",
+      "teams": [
+        "Netherlands",
+        "Denmark",
+        "Japan",
+        "Cameroon"
+      ]
+    },
+    {
+      "name": "Group F",
+      "teams": [
+        "Italy",
+        "Paraguay",
+        "New Zealand",
+        "Slovakia"
+      ]
+    },
+    {
+      "name": "Group G",
+      "teams": [
+        "Ivory Coast",
+        "Portugal",
+        "Brazil",
+        "North Korea"
+      ]
+    },
+    {
+      "name": "Group H",
+      "teams": [
+        "Honduras",
+        "Chile",
+        "Spain",
+        "Switzerland"
+      ]
+    }
+  ]
+}

data/2010/worldcup.meta.json

@@ -0,0 +1,8 @@
+{
+  "host": "South Africa",
+  "teams_count": 32,
+  "winner": "Spain",
+  "runner_up": "Netherlands",
+  "third_place": "Germany",
+  "fourth_place": "Uruguay"
+}

data/2010/worldcup.stadiums.json

@@ -0,0 +1,44 @@
+{
+  "stadiums": [
+    {
+      "name": "Nelson Mandela Bay Stadium",
+      "city": "Port Elizabeth"
+    },
+    {
+      "name": "Royal Bafokeng Stadium",
+      "city": "Rustenburg"
+    },
+    {
+      "name": "Free State Stadium",
+      "city": "Bloemfontein"
+    },
+    {
+      "name": "Soccer City",
+      "city": "Johannesburg"
+    },
+    {
+      "name": "Moses Mabhida Stadium",
+      "city": "Durban"
+    },
+    {
+      "name": "Ellis Park Stadium",
+      "city": "Johannesburg"
+    },
+    {
+      "name": "Loftus Versfeld Stadium",
+      "city": "Pretoria"
+    },
+    {
+      "name": "Cape Town Stadium",
+      "city": "Cape Town"
+    },
+    {
+      "name": "Peter Mokaba Stadium",
+      "city": "Polokwane"
+    },
+    {
+      "name": "Mbombela Stadium",
+      "city": "Nelspruit"
+    }
+  ]
+}