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>

includes/bootstrap.php

@@ -767,6 +767,50 @@ function dbnToolsIsFreeTier(): bool
         && !empty($_SESSION['dbn_tools_sso_uid']);
 }
 
+/**
+ * Current free-tier SSO user id, or 0 for CaveauAI / non-SSO sessions.
+ * Lets an endpoint resolve a quality tier (subscription gate) BEFORE charging,
+ * without reaching into the session directly. Mirrors the uid the check/deduct
+ * helpers use.
+ */
+function dbnToolsFreeTierUid(): int
+{
+    return dbnToolsIsFreeTier() ? (int)$_SESSION['dbn_tools_sso_uid'] : 0;
+}
+
+/**
+ * Resolve the model + credit gate for a tool run. When the request carries a `tier`
+ * param, honour the Quick/Pro quality tier (subscription-gated, server-priced); otherwise
+ * fall back to the legacy engine-selector behaviour. Runs the credit gate (exits 402/429
+ * if over limit) and returns the context an endpoint needs to run + deduct.
+ *
+ * @return array{tier:string,engine:string,credits:?int,ftUid:int,metadata:array}
+ */
+function dbnToolsResolveToolRun(string $tool, array $input, string $legacyDefaultEngine = 'azure_mini'): array
+{
+    if (isset($input['tier'])) {
+        $res   = ToolModels::resolveTier(dbnToolsFreeTierUid(), $tool, (string)$input['tier']);
+        $ftUid = dbnToolsFreeTierCheckAmount($tool, $res['credits']);
+        return [
+            'tier'     => $res['tier'],
+            'engine'   => $res['engine'],
+            'credits'  => $res['credits'],
+            'ftUid'    => $ftUid,
+            'metadata' => ['tier' => $res['tier'], 'engine' => $res['engine']],
+        ];
+    }
+
+    $ftUid  = dbnToolsFreeTierCheck($tool);
+    $engine = ToolModels::engineForUser($ftUid, (string)($input['engine'] ?? $legacyDefaultEngine));
+    return [
+        'tier'     => '',
+        'engine'   => $engine,
+        'credits'  => null,
+        'ftUid'    => $ftUid,
+        'metadata' => [],
+    ];
+}
+
 /**
  * Enforce credit + tier gate before a tool call.
  * Exits with JSON 402/429 if the user is over limit or out of credits.