feat(tools): converge two-tier Quick/Pro selector onto .no fork

Port the dobetterlegal-tools two-tier quality stack to dobetternorge.no:
QUALITY_TIERS registry + resolveTier (ToolModels), dbnToolsResolveToolRun
(bootstrap), tier read+charge in the 6 analytical endpoints, Quick/Pro
UI + payload.tier on the 6 tool pages/JS, and the bounded
corpusContextForSummarize RAG fix (per-passage trim + total budget +
reranker_enabled). Back-compat: requests without `tier` keep legacy
engine behavior.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

api/discrepancy.php

@@ -41,7 +41,23 @@ try {
     }
 
     $language      = dbnToolsNormalizeLanguage($input['language'] ?? 'en');
-    $engine        = ToolModels::engineForUser($ftUid, (string)($input['engine'] ?? 'azure_mini'));
+    if (isset($input['tier'])) {
+        $run         = ToolModels::resolveTier(dbnToolsFreeTierUid(), 'discrepancy', (string)$input['tier']);
+        $engine      = $run['engine'];
+        $tierCredits = $run['credits'];
+        $tierMeta    = ['tier' => $run['tier'], 'engine' => $engine];
+        if ($ftUid > 0) {
+            $gate = FreeTier::checkAmount($ftUid, 'discrepancy', $tierCredits);
+            if (empty($gate['ok'])) {
+                $emit('error', ['code' => $gate['reason'] ?? 'no_credits', 'message' => 'Insufficient credits for the selected tier.']);
+                exit;
+            }
+        }
+    } else {
+        $engine      = ToolModels::engineForUser($ftUid, (string)($input['engine'] ?? 'azure_mini'));
+        $tierCredits = null;
+        $tierMeta    = [];
+    }
     $sliceInput    = $input['slices'] ?? [];
 
     // Extract file A
@@ -144,7 +160,9 @@ try {
         'deployment'     => $result['trace_metadata']['deployment'] ?? null,
     ]);
 
-    $ftRemaining = dbnToolsFreeTierDeduct($ftUid, 'discrepancy');
+    $ftRemaining = $tierCredits === null
+        ? dbnToolsFreeTierDeduct($ftUid, 'discrepancy')
+        : dbnToolsFreeTierDeductAmount($ftUid, 'discrepancy', $tierCredits, $tierMeta);
     if ($ftRemaining >= 0) {
         $result['balance'] = $ftRemaining;
     }