chore: docker, config, delivery sinks, dialogue, and agent docs

- Dockerfile: multi-stage build with CGO_ENABLED=0, embedder model copy,
  non-root user, healthcheck, and /data volume.
- docker-compose.yml: mavend + mavweb services with shared volume, health
  checks, and restart policy.
- .gitignore: ignore models/llm/*.gguf, deploy/telegram.env, tmp artifacts.
- deploy/mavend.json: add LLM, phraser, voice sections (embedder, model
  paths, wake sensitivity). Add telegram token env-var expansion.
- deploy/telegram.env.example: template for telegram bot token.
- internal/config/config.go: add LLM config struct, voice config struct
  (embedder, llama, wake sensitivity), telegram token loading.
- telegramsink: add chat intent delivery support alongside existing types.
- voicesink: skip empty payloads in delivery.
- dialogue/session: add chat intent to anaphora resolution, test coverage.
- AGENTS.md: update with LLM embedder, LFM model download/configure steps,
  new UI conventions.
- REARCH.md: architecture research document.
- cmd/mavend/main.go: wire LLM config, phraser, embedder, telegram config,
  WebAuthn, IPC event/routine handlers, and reactive notes.

.gitignore

@@ -24,6 +24,8 @@ deps/
 
 # Deploy secret (the at-rest db key) — never commit
 deploy/db_key.env
+# Deploy secret (telegram bot token + chat id) — never commit
+deploy/telegram.env
 
 # Temp files
 /tmp/