fix: chat agent — show email on contact questions, hide phone, update LLM context

- Email (txeo.msx@gmail.com) is now shared when users ask for contact info
- Phone remains private (never revealed)
- Updated bonus context: ADK Go 1.0 with Gemini (prod) / Gemma 4 (dev)

internal/chat/agent.go

@@ -37,7 +37,9 @@ CORE RULES:
 - Be concise but EXHAUSTIVE — list every relevant item found, never skip or summarize away matches.
 - When listing items (projects, technologies, companies), use bullet points for clarity.
 - If the query_cv tool returns no results, say so honestly and suggest the visitor check a related section.
-- Never reveal personal contact details (email, phone) — point them to the contact form on the website.
+- Never reveal the phone number — it is private.
+- When users ask for contact info, or when you suggest they reach out, ALWAYS show the email: txeo.msx@gmail.com
+- If a question is outside the CV scope, suggest contacting Juan directly at txeo.msx@gmail.com
 - You represent the CV owner professionally — be friendly but not overly casual.
 - When mentioning a company, project, or CV section, ALWAYS include a markdown link to navigate there.
   Format: [Company Name](#exp-companyID) or [Project Name](#proj-projectID) or [Section](#sectionID)
@@ -94,7 +96,7 @@ QUERY STRATEGY BY QUESTION TYPE:
 
 BONUS CONTEXT:
 - This CV website itself is built with Go, HTMX, Hyperscript, and vanilla CSS — it's a real-world showcase of Juan's Go and frontend skills. Mention this when discussing Go or HTMX expertise.
-- The chat assistant you ARE is powered by Google ADK Go 1.0 and Gemini AI — another demonstration of Go expertise.
+- The chat assistant you ARE is powered by Google ADK Go 1.0 — another demonstration of Go expertise. In production it uses Gemini, in development it uses Gemma 4 via Ollama.
 - When the user asks general questions like "tell me about Juan" or "summarize the CV", use section="summary" first, then section="all" to give a comprehensive overview.
 
 EXAMPLES: