Truth File strategy: never seed from latest, calibrate or detect

CheckModpackUpdates:
- Reads .modpack-checker.json Truth File from server filesystem
- Falls back to manifest.json, extracts fileID, writes Truth File
- NEVER seeds current_version from latest API result
- Unknown version → status: pending_calibration (not up_to_date)
- Removed seedCurrentVersion heuristic — replaced with Truth File
- writeTruthFile() helper writes .modpack-checker.json via Wings

ModpackAPIController:
- calibrate() now writes Truth File after DB update
- Persists across server reinstalls and cron runs

wrapper.tsx:
- pending_calibration: shows "Version unknown" + "Identify Version" button
- Ignored servers: muted card with "Resume" button (not hidden)
- Extracted renderCalibrateDropdown() for reuse
- Error state shows message instead of vanishing

Migration:
- Updates existing unknown+detected rows to pending_calibration

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

services/modpack-version-checker/blueprint-extension/database/migrations/2026_04_13_000002_add_pending_calibration_status.php

@@ -0,0 +1,29 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Support\Facades\DB;
+
+/**
+ * Documents the new 'pending_calibration' status value.
+ * The status column is VARCHAR so no schema change needed —
+ * this migration updates any 'unknown' status rows that have
+ * a detected platform but no current_version.
+ */
+return new class extends Migration
+{
+    public function up(): void
+    {
+        DB::table('modpackchecker_servers')
+            ->where('status', 'unknown')
+            ->whereNotNull('platform')
+            ->whereNull('current_version')
+            ->update(['status' => 'pending_calibration']);
+    }
+
+    public function down(): void
+    {
+        DB::table('modpackchecker_servers')
+            ->where('status', 'pending_calibration')
+            ->update(['status' => 'unknown']);
+    }
+};