refactor(routing): rename local/claude to fast/thinking model pair

The routing decision is about reasoning capacity, not cost or provider.
Fast model (koala/qwen35-9b-fast) handles high-pass-rate calls; thinking
model (iguana/gemma4-26b) handles low-pass-rate calls. Removes the
implicit Anthropic dependency from the routing pod — both models go
through LiteLLM.

Renames: HYPERGUILD_LOCAL_MODEL → HYPERGUILD_FAST_MODEL,
HYPERGUILD_CLAUDE_MODEL → HYPERGUILD_THINKING_MODEL,
Router.LocalModel → FastModel, Router.ClaudeModel → ThinkingModel,
log decision "claude_fallback" → "thinking_fallback".

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/routing/log.go

@@ -13,7 +13,7 @@ import (
 type LogEntry struct {
 	SessionID   string
 	Skill       string // the original skill the call routed (e.g., "review")
-	Decision    string // "local" or "claude" or "claude_fallback"
+	Decision    string // "local" or "thinking" or "thinking_fallback"
 	Message     string // free-form, e.g. "model=qwen35, pass_rate=0.94"
 	ProjectRoot string
 	DurationMs  int64

internal/routing/router.go

@@ -24,8 +24,8 @@ type Router struct {
 	Fetcher     *Fetcher
 	Logger      *Logger
 	Policy      Policy
-	LocalModel  string
-	ClaudeModel string
+	FastModel     string
+	ThinkingModel string
 	Complete    CompleteFunc
 }
 
@@ -40,9 +40,9 @@ func (r *Router) Run(ctx context.Context, in RunInput) (string, int64, error) {
 	hash := CanonicalHash(in.System, in.User)
 	decision := r.Policy.Decide(pr, hash)
 
-	model := r.ClaudeModel
+	model := r.ThinkingModel
 	if decision == DecideLocal {
-		model = r.LocalModel
+		model = r.FastModel
 	}
 
 	out, ms, err := r.Complete(ctx, model, in.System, in.User)
@@ -59,13 +59,13 @@ func (r *Router) Run(ctx context.Context, in RunInput) (string, int64, error) {
 	}
 
 	if err != nil && decision == DecideLocal {
-		slog.Warn("router: local failed, falling open to claude", "skill", in.Skill, "err", err)
-		out, ms, err = r.Complete(ctx, r.ClaudeModel, in.System, in.User)
+		slog.Warn("router: fast failed, falling open to thinking model", "skill", in.Skill, "err", err)
+		out, ms, err = r.Complete(ctx, r.ThinkingModel, in.System, in.User)
 		if lerr := r.Logger.LogDecision(ctx, LogEntry{
 			SessionID:   in.SessionID,
 			Skill:       in.Skill,
-			Decision:    "claude_fallback",
-			Message:     fmt.Sprintf("model=%s, after-local-error", r.ClaudeModel),
+			Decision:    "thinking_fallback",
+			Message:     fmt.Sprintf("model=%s, after-fast-error", r.ThinkingModel),
 			ProjectRoot: in.ProjectRoot,
 			DurationMs:  ms,
 			Failed:      err != nil,

internal/routing/router_test.go

@@ -49,12 +49,12 @@ func newRouter(t *testing.T, llm *fakeLLM, passRate float64) (*routing.Router, *
 	t.Cleanup(brain.Close)
 
 	r := &routing.Router{
-		Fetcher:     routing.NewFetcher(brain.URL, "7d", time.Minute),
-		Logger:      routing.NewLogger(brain.URL),
-		Policy:      routing.Policy{Floor: 0.9, Ceil: 0.7},
-		LocalModel:  "qwen35",
-		ClaudeModel: "claude-sonnet-4-6",
-		Complete:    llm.Complete,
+		Fetcher:       routing.NewFetcher(brain.URL, "7d", time.Minute),
+		Logger:        routing.NewLogger(brain.URL),
+		Policy:        routing.Policy{Floor: 0.9, Ceil: 0.7},
+		FastModel:     "koala/qwen35-9b-fast",
+		ThinkingModel: "iguana/gemma4-26b",
+		Complete:      llm.Complete,
 	}
 	return r, brain, brain
 }
@@ -72,10 +72,10 @@ func TestRouterRoutesLocalAtHighPassRate(t *testing.T) {
 	llm.mu.Lock()
 	defer llm.mu.Unlock()
 	require.Len(t, llm.calls, 1)
-	assert.Equal(t, "qwen35", llm.calls[0].Model)
+	assert.Equal(t, "koala/qwen35-9b-fast", llm.calls[0].Model)
 }
 
-func TestRouterRoutesClaudeAtLowPassRate(t *testing.T) {
+func TestRouterRoutesThinkingAtLowPassRate(t *testing.T) {
 	llm := &fakeLLM{resp: "ok"}
 	r, _, _ := newRouter(t, llm, 0.3)
 
@@ -87,12 +87,12 @@ func TestRouterRoutesClaudeAtLowPassRate(t *testing.T) {
 	llm.mu.Lock()
 	defer llm.mu.Unlock()
 	require.Len(t, llm.calls, 1)
-	assert.Equal(t, "claude-sonnet-4-6", llm.calls[0].Model)
+	assert.Equal(t, "iguana/gemma4-26b", llm.calls[0].Model)
 }
 
-func TestRouterFailsOpenLocalErrorToClaude(t *testing.T) {
-	llm := &fakeLLM{resp: "ok-after-fallback", err: errors.New("local boom"), errOn: "qwen35"}
-	r, _, _ := newRouter(t, llm, 0.95) // would route local
+func TestRouterFailsOpenFastErrorToThinking(t *testing.T) {
+	llm := &fakeLLM{resp: "ok-after-fallback", err: errors.New("fast boom"), errOn: "koala/qwen35-9b-fast"}
+	r, _, _ := newRouter(t, llm, 0.95) // would route fast
 
 	out, _, err := r.Run(context.Background(), routing.RunInput{
 		Skill: "review", System: "sys", User: "user", SessionID: "s3",
@@ -103,12 +103,12 @@ func TestRouterFailsOpenLocalErrorToClaude(t *testing.T) {
 	llm.mu.Lock()
 	defer llm.mu.Unlock()
 	require.Len(t, llm.calls, 2)
-	assert.Equal(t, "qwen35", llm.calls[0].Model)
-	assert.Equal(t, "claude-sonnet-4-6", llm.calls[1].Model)
+	assert.Equal(t, "koala/qwen35-9b-fast", llm.calls[0].Model)
+	assert.Equal(t, "iguana/gemma4-26b", llm.calls[1].Model)
 }
 
-func TestRouterDefaultsToLocalWhenBrainUnreachable(t *testing.T) {
-	// Brain returns 500 → fetcher errors → router treats pass rate as nil → local.
+func TestRouterDefaultsToFastWhenBrainUnreachable(t *testing.T) {
+	// Brain returns 500 → fetcher errors → router treats pass rate as nil → fast.
 	brain := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
 		http.Error(w, "down", http.StatusInternalServerError)
 	}))
@@ -116,12 +116,12 @@ func TestRouterDefaultsToLocalWhenBrainUnreachable(t *testing.T) {
 
 	llm := &fakeLLM{resp: "ok"}
 	r := &routing.Router{
-		Fetcher:     routing.NewFetcher(brain.URL, "7d", time.Minute),
-		Logger:      routing.NewLogger(brain.URL),
-		Policy:      routing.Policy{Floor: 0.9, Ceil: 0.7},
-		LocalModel:  "qwen35",
-		ClaudeModel: "claude-sonnet-4-6",
-		Complete:    llm.Complete,
+		Fetcher:       routing.NewFetcher(brain.URL, "7d", time.Minute),
+		Logger:        routing.NewLogger(brain.URL),
+		Policy:        routing.Policy{Floor: 0.9, Ceil: 0.7},
+		FastModel:     "koala/qwen35-9b-fast",
+		ThinkingModel: "iguana/gemma4-26b",
+		Complete:      llm.Complete,
 	}
 
 	_, _, err := r.Run(context.Background(), routing.RunInput{
@@ -132,5 +132,5 @@ func TestRouterDefaultsToLocalWhenBrainUnreachable(t *testing.T) {
 	llm.mu.Lock()
 	defer llm.mu.Unlock()
 	require.Len(t, llm.calls, 1)
-	assert.Equal(t, "qwen35", llm.calls[0].Model)
+	assert.Equal(t, "koala/qwen35-9b-fast", llm.calls[0].Model)
 }