Word nudges from templates by default, model optional

DEPRECATION, flagged not asked: LLM-phrased nudges are no longer the default.
LLMPhraser.PhraseNudge now returns a hand-written Russian template. The model
still phrases chat, queries and reminders — only nudges moved.

Why: measured over many runs, Qwen3.5-0.8B wrote formal "вы" and plural
imperatives, used masculine self-reference, and invented facts and units
(90-95 seconds to boil an egg). A nudge is five words of known content, so
generation buys nothing and risks the persona every time. Templates score
15/15 on the nudge fixture, the model 11-13/15.

Nothing is deleted: the prompt, the fallbacks and the whole LLM nudge path
stay. Set phraser.llm_nudges = true in deploy/mavend.json to get them back.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CGeSZxh1DCtRxmFVSYVGvJ

internal/phraser/grammar_test.go

@@ -35,6 +35,8 @@ func newGrammarSpy(t *testing.T) *grammarSpy {
 }
 
 // callAllPhrasingPaths hits every path that expects the JSON contract.
+// LLMNudges must be set on the phraser under test: nudges come from templates
+// by default and never reach the model at all.
 func callAllPhrasingPaths(t *testing.T, p *LLMPhraser) {
 	t.Helper()
 	ctx := context.Background()
@@ -58,7 +60,7 @@ func TestGrammarIsAttachedToEveryPhrasingRequest(t *testing.T) {
 		t.Fatal("responseGrammar is empty")
 	}
 	spy := newGrammarSpy(t)
-	p := NewLLMPhraserAt(spy.srv.URL, Config{})
+	p := NewLLMPhraserAt(spy.srv.URL, Config{LLMNudges: true})
 
 	callAllPhrasingPaths(t, p)
 
@@ -74,7 +76,7 @@ func TestGrammarIsAttachedToEveryPhrasingRequest(t *testing.T) {
 
 func TestNoGrammarConfigDisablesIt(t *testing.T) {
 	spy := newGrammarSpy(t)
-	p := NewLLMPhraserAt(spy.srv.URL, Config{NoGrammar: true})
+	p := NewLLMPhraserAt(spy.srv.URL, Config{NoGrammar: true, LLMNudges: true})
 
 	callAllPhrasingPaths(t, p)