feat(redact): tag highlighting, inventory panel, before/after toggle, gpt-4o upgrade

- CSS: colour-coded [TAG] spans by entity type (person=pink, org=blue,
  place=green, date=amber, id=purple)
- Inventory panel: collapsible list showing tag → original text mappings
  with occurrence counts, sourced from new redaction_map API response key
- Before/after toggle: Redacted / Original view-switch buttons wired to
  lastOriginalText captured at submission time
- One-click gpt-4o upgrade button when mini or GPU engine was used
- Backend: redaction_map built from applied LLM entities (tag → originals
  + occurrence count via substr_count on final text)
- renderResults now calls setupRedactViewToggle() after DOM is written

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

includes/LegalTools.php

@@ -512,6 +512,7 @@ PROMPT;
         $finalRedacted = $preRedacted;
         $pass2Counts   = [];
         $llmDeployment = null;
+        $redactionMap  = [];
 
         $llmResult = $this->llmRedactionPass(
             $preRedacted, $language, $aliases, $engine,
@@ -527,6 +528,7 @@ PROMPT;
             $entities      = $llmResult['entities'] ?? [];
             $llmDeployment = $llmResult['deployment'] ?? null;
             $applied       = 0;
+            $redactionMap  = [];
 
             foreach ($entities as $entity) {
                 if (!is_array($entity)) {
@@ -549,14 +551,32 @@ PROMPT;
                     $finalRedacted = $replaced;
                     $pass2Counts[$type] = ($pass2Counts[$type] ?? 0) + 1;
                     $applied++;
+                    if (!isset($redactionMap[$tag])) {
+                        $redactionMap[$tag] = ['originals' => [], 'type' => $type];
+                    }
+                    if (!in_array($original, $redactionMap[$tag]['originals'], true)) {
+                        $redactionMap[$tag]['originals'][] = $original;
+                    }
                 } elseif (str_contains($finalRedacted, $original)) {
                     // Fallback for names adjacent to punctuation or non-word characters
                     $finalRedacted = str_replace($original, $tag, $finalRedacted);
                     $pass2Counts[$type] = ($pass2Counts[$type] ?? 0) + 1;
                     $applied++;
+                    if (!isset($redactionMap[$tag])) {
+                        $redactionMap[$tag] = ['originals' => [], 'type' => $type];
+                    }
+                    if (!in_array($original, $redactionMap[$tag]['originals'], true)) {
+                        $redactionMap[$tag]['originals'][] = $original;
+                    }
                 }
             }
 
+            // Add occurrence counts by scanning the final text
+            foreach ($redactionMap as $tag => &$entry) {
+                $entry['occurrences'] = substr_count($finalRedacted, $tag);
+            }
+            unset($entry);
+
             $pass2Detail = $applied > 0
                 ? "{$applied} additional: " . implode(', ', array_map(fn($k, $v) => "{$k}: {$v}", array_keys($pass2Counts), $pass2Counts))
                 : 'no additional entities found';
@@ -592,6 +612,7 @@ PROMPT;
             'redacted_text'              => $finalRedacted,
             'detected_entity_categories' => $categories,
             'entity_counts'              => $allCounts,
+            'redaction_map'              => $redactionMap,
             'evidence_trail'             => [['title' => 'Pasted text', 'excerpt' => 'Processed in-memory only; not stored.']],
             'what_remains_uncertain'     => ['Human review is still recommended for contextual identification.'],
             'next_practical_step'        => 'Review the output and rerun in strict mode if the text will be shared broadly.',