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>

assets/js/barnevernet.js

@@ -55,7 +55,7 @@
       roleCustom:     document.getElementById('bvjRoleCustom'),
       slices:         Array.from(document.querySelectorAll('.adv-slice')),
       langButtons:    Array.from(document.querySelectorAll('#bvjLangSwitcher .lang-btn')),
-      engineRadios:   Array.from(document.querySelectorAll('input[name="bvjEngine"]')),
+      tierRadios:     Array.from(document.querySelectorAll('input[name="bvjTier"]')),
       subQ:           document.getElementById('bvjSubQ'),
       subQVal:        document.getElementById('bvjSubQValue'),
       chunkLimit:     document.getElementById('bvjChunkLimit'),
@@ -186,9 +186,9 @@
     };
   }
 
-  function getEngine() {
-    const checked = els.engineRadios.find((r) => r.checked);
-    return checked ? checked.value : 'azure_mini';
+  function getTier() {
+    const checked = els.tierRadios.find((r) => r.checked);
+    return checked ? checked.value : 'quick';
   }
 
   // ── File upload ────────────────────────────────────────────────────────────
@@ -385,13 +385,11 @@
       return;
     }
 
-    const engine = getEngine();
+    const tier = getTier();
     const additionalNotes = (els.notes ? els.notes.value : '').trim();
-    const expectedDuration = engine === 'azure_full'
-      ? '90–180 seconds with Azure gpt-4o'
-      : (engine === 'gpu' ? '45–90 seconds on GPU'
-      : (engine === 'dbn_legal' ? '60–120 seconds with Norwegian specialist'
-      : '30–60 seconds with Azure gpt-4o-mini'));
+    const expectedDuration = tier === 'pro'
+      ? '90–180 seconds with Claude Sonnet'
+      : '30–60 seconds with Claude Haiku';
 
     setStatus(`Analysing document for ${advocateRole}… (${expectedDuration})`, 'busy');
     els.runButton.disabled = true;
@@ -403,7 +401,7 @@
 
     const payload = {
       advocate_role:    advocateRole,
-      engine,
+      tier,
       language:         lang,
       slices,
       controls:         getControls(),