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>

includes/tool_form.php

@@ -19,6 +19,13 @@
                         <input type="number" id="numSpeakersInput" name="num_speakers" min="2" max="10" placeholder="auto" class="num-speakers-input" aria-label="Expected speaker count">
                     </div>
 
+                    <div class="control-row is-hidden" id="personaControl">
+                        <span class="control-label">Domain</span>
+                        <label class="persona-select-label" for="personaSelect">
+                            <select id="personaSelect" name="profile" aria-label="Legal domain persona"></select>
+                        </label>
+                    </div>
+
                     <div class="control-row is-hidden" id="corpusScopeControl">
                         <span class="control-label">Search</span>
                         <label><input type="radio" name="corpusScope" value="both" checked> Legal Library + My Docs</label>