refactor: migrate to new ensemble model and improve test coverage

- Replaced usage of entity.SuggestModel with ensemble.Ensemble to streamline prediction logic
- Renamed Ensemble.NextPredict to ProgressivePredict for clarity and consistency
- Refactored and consolidated alias store logic into a single file with test coverage
- Switched logging from custom log levels to slog for structured logging and cleaner API
- Added unit tests for freq, prefix, ensemble, alias, llm, meta, and migration modules
- Removed unused eval.go_ and legacy alias store files

Author: trknhr

cmd/benchmark/profile.go

@@ -15,6 +15,7 @@ import (
 	"github.com/trknhr/ghosttype/cmd/eval"
 	"github.com/trknhr/ghosttype/internal/history"
 	"github.com/trknhr/ghosttype/internal/model"
+	"github.com/trknhr/ghosttype/internal/model/ensemble"
 	"github.com/trknhr/ghosttype/internal/model/entity"
 	"github.com/trknhr/ghosttype/internal/ollama"
 	"github.com/trknhr/ghosttype/internal/store"
@@ -705,7 +706,7 @@ func runAllProfileTypes(db *sql.DB) error {
 // NOTE: For accurate measurement, this requires instrumenting the actual
 // DB and network clients, for example by wrapping sql.DB and http.Client.
 type InstrumentedEnsemble struct {
-	model       entity.SuggestModel
+	model       *ensemble.Ensemble
 	dbTime      time.Duration
 	networkTime time.Duration
 	mu          sync.Mutex
@@ -716,7 +717,7 @@ type ModelTimings struct {
 	NetworkTime time.Duration
 }
 
-func createInstrumentedEnsemble(originalModel entity.SuggestModel) *InstrumentedEnsemble {
+func createInstrumentedEnsemble(originalModel *ensemble.Ensemble) *InstrumentedEnsemble {
 	return &InstrumentedEnsemble{
 		model: originalModel,
 	}

cmd/eval/batch-eval.go

@@ -9,7 +9,7 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/trknhr/ghosttype/internal/history"
 	"github.com/trknhr/ghosttype/internal/model"
-	"github.com/trknhr/ghosttype/internal/model/entity"
+	"github.com/trknhr/ghosttype/internal/model/ensemble"
 	"github.com/trknhr/ghosttype/internal/ollama"
 	"github.com/trknhr/ghosttype/internal/store"
 )
@@ -103,7 +103,7 @@ func RunBatchEvaluation(db *sql.DB, filePath string, modelNames []string) error
 	return nil
 }
 
-func runSingleModelEvaluation(model entity.SuggestModel, cases []EvaluationCase) (EvaluationResult, error) {
+func runSingleModelEvaluation(model *ensemble.Ensemble, cases []EvaluationCase) (EvaluationResult, error) {
 	result := EvaluationResult{
 		ByCategory: make(map[string]CategoryResult),
 	}

cmd/eval/eval.go_

@@ -0,0 +1,36 @@
+package history_test
+
+import (
+	"os"
+	"testing"
+
+	"github.com/trknhr/ghosttype/internal/history"
+)
+
+func TestDetectShell(t *testing.T) {
+	tests := []struct {
+		name     string
+		shellEnv string
+		want     string
+	}{
+		{"Zsh", "/bin/zsh", "zsh"},
+		{"Bash", "/usr/bin/bash", "bash"},
+		{"Fish", "/usr/local/bin/fish", "fish"},
+		{"PowerShell", "/usr/bin/pwsh", "powershell"},
+		{"PowerShell full", "/usr/bin/powershell", "powershell"},
+		{"Unknown", "/bin/foobar", "unknown"},
+		{"Empty", "", "unknown"},
+	}
+
+	original := os.Getenv("SHELL") // 元の値を保存
+	defer os.Setenv("SHELL", original)
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			os.Setenv("SHELL", tt.shellEnv)
+			if got := history.DetectShell(); got != tt.want {
+				t.Errorf("DetectShell() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}