Wire voice-tapped facts into entity resolution; fix phraser model config

WriteFactReq gains an optional Subject field (empty = old behavior,
no CoreAPI signature change) and the IntentFact handler now passes the
fact's key as its resolution subject, so voice-tapped facts flow into
the Vikunja #279 enrichment queue automatically.

Also: deploy/mavend.json's phraser was pointed at a 4B model with
n_gpu_layers=99, which OOM'd under memory pressure and left a zombie
llama-server child. Swapped to the 2B Qwen model matching the intended
resident-model size, keeping GPU offload.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018ghELqYhZNLub2TXGMazqA

internal/ipc/server.go

@@ -36,7 +36,7 @@ func (a *storeAPI) WriteFact(ctx context.Context, req WriteFactReq) (int64, erro
 	if req.VoidsID != nil {
 		voids = sql.NullInt64{Int64: *req.VoidsID, Valid: true}
 	}
-	id, err := a.s.WriteFact(ctx, req.Ts, store.FactKind(req.Kind), req.Key, req.Value, req.Source, req.Confidence, voids)
+	id, err := a.s.WriteFactAboutSubject(ctx, req.Ts, store.FactKind(req.Kind), req.Key, req.Subject, req.Value, req.Source, req.Confidence, voids)
 	return id, mapErr(err)
 }