feat(techniques): status hover tooltips + min 2 tests for validated

1. Status logic (v3): require ≥2 validated tests with 'detected' result
   to reach 'validated' status. With only 1 validated+detected test the
   technique stays 'partial' (single test is insufficient evidence).
   Backfilled existing data: T1012 and T1059.001 downgraded to 'partial'.

2. Hover tooltips on status badges in TechniquesPage and TechniqueDetailPage:
   - validated: ≥2 tests executed and detected
   - partial: some tests done but incomplete coverage
   - in_progress: tests exist but none validated yet
   - not_covered: tests run but Blue Team didn't detect
   - not_evaluated: no tests created yet
   - review_required: recent update needs acknowledgment

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

frontend/src/pages/TechniqueDetailPage.tsx

@@ -27,6 +27,15 @@ import { useAuth } from "../context/AuthContext";
 import TestFromTemplateForm from "../components/TestFromTemplateForm";
 import type { TechniqueStatus, TestState, TestResult } from "../types/models";
 
+const STATUS_TOOLTIPS: Record<TechniqueStatus, string> = {
+  validated:      "✅ Validated — ≥2 tests executed and detected by Blue Team. Technique is covered.",
+  partial:        "🟡 Partial — Some tests done but not all detected, only 1 validated test, or some tests still pending. More testing needed.",
+  in_progress:    "🔵 In Progress — Tests exist but none validated yet (draft, executing, or under review).",
+  not_covered:    "🔴 Not Covered — Tests were run but Blue Team did not detect the attack. Coverage gap.",
+  not_evaluated:  "⚫ Not Evaluated — No tests created for this technique yet.",
+  review_required:"🟠 Review Required — Technique was recently updated or new intel/rules detected. Needs review.",
+};
+
 const statusBadgeColors: Record<TechniqueStatus, string> = {
   validated: "bg-green-900/50 text-green-400 border-green-500/30",
   partial: "bg-yellow-900/50 text-yellow-400 border-yellow-500/30",
@@ -243,9 +252,10 @@ export default function TechniqueDetailPage() {
               <div className="flex items-center gap-3">
                 <h1 className="text-2xl font-bold text-white">{technique.mitre_id}</h1>
                 <span
-                  className={`inline-flex rounded-full border px-2.5 py-0.5 text-xs font-medium ${
+                  className={`inline-flex rounded-full border px-2.5 py-0.5 text-xs font-medium cursor-help ${
                     statusBadgeColors[technique.status_global]
                   }`}
+                  title={STATUS_TOOLTIPS[technique.status_global]}
                 >
                   {technique.status_global.replace(/_/g, " ")}
                 </span>