feat(tools): persona-driven multi-domain corpus + model routing

Generalize the family-locked legal tools into caveauAI persona profiles
(client 57 chat profiles, resolved in-process via the chat_profiles bridge).
Each tool accepts an optional `profile` slug that scopes the corpus package(s),
search method, system prompt and synthesis model; omitting it falls back to the
family-legal package so existing behaviour is unchanged.

- dbnToolsResolvePersona / dbnToolsListPersonas / dbnToolsBootChatProfiles in
  bootstrap.php; new api/personas.php + dbn.list_personas MCP tool.
- LegalTools search/ask/corpusContextForSummarize and the BvjAnalyzer /
  LegalAnalysis / translate paths take the persona's packages + prompt + model.
- Persona <select> on ask/search/summarize (populated from api/personas.php).

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

api/legal-analysis.php

@@ -55,7 +55,16 @@ try {
         'chars'    => mb_strlen($text, 'UTF-8'),
     ]);
 
-    $agent = new DbnLegalAnalysisAgent();
+    // Resolve the persona (default = child-welfare for this barnevern tool) so
+    // the targeted legal-check step uses the persona's system prompt + model.
+    $client          = dbnToolsRequireClient();
+    $personaSlug     = (isset($input['profile']) && is_string($input['profile']) && trim($input['profile']) !== '')
+        ? trim($input['profile'])
+        : 'child-welfare';
+    $personaResolved = dbnToolsResolvePersona((int)$client['id'], $personaSlug);
+
+    $agent = (new DbnLegalAnalysisAgent())
+        ->withPersonaPrompt($personaResolved['system_prompt'] ?? null);
 
     // Pass 1 — extract issues (Azure, fast); deduct credit AFTER this succeeds
     $emit('progress', ['step' => 'extracting_issues', 'detail' => 'Identifying distinct legal issues…']);
@@ -101,7 +110,7 @@ try {
             'issue_id' => $issue['id'],
         ]);
         $corpusQuery   = $issue['question'] . "\n" . $issue['brief_context'];
-        $corpusContext = $svc->corpusContextForSummarize($corpusQuery, 3);
+        $corpusContext = $svc->corpusContextForSummarize($corpusQuery, 3, $personaResolved['slug'] ?? null);
 
         $emit('progress', [
             'step'     => 'issue_answering',
@@ -122,7 +131,8 @@ try {
     try {
         $legalCheck = dbnToolsRunLegalCheck(
             mb_strimwidth((string)($synth['overall_assessment'] ?? ''), 0, 800),
-            $docType
+            $docType,
+            $personaResolved['system_prompt'] ?? null
         );
     } catch (Throwable) {}