ci: goimports blank-line before local-prefix group across remaining files

Run goimports across the tree so every file has the expected blank
line between third-party and the vectorless-engine local group.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: hallelx2

cmd/engine/main.go

@@ -21,6 +21,7 @@ import (
 	"github.com/hallelx2/llmgate/provider/anthropic"
 	"github.com/hallelx2/llmgate/provider/gemini"
 	"github.com/hallelx2/llmgate/provider/openai"
+
 	"github.com/hallelx2/vectorless-engine/internal/api"
 	"github.com/hallelx2/vectorless-engine/pkg/config"
 	"github.com/hallelx2/vectorless-engine/pkg/db"

pkg/retrieval/retrieval_test.go

@@ -9,6 +9,7 @@ import (
 	"testing"
 
 	"github.com/hallelx2/llmgate"
+
 	"github.com/hallelx2/vectorless-engine/pkg/retrieval"
 	"github.com/hallelx2/vectorless-engine/pkg/tree"
 )

pkg/retrieval/single_pass.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	"github.com/hallelx2/llmgate"
+
 	"github.com/hallelx2/vectorless-engine/pkg/tree"
 )
 

pkg/retrieval/splitter.go

@@ -6,6 +6,7 @@ import (
 	"strings"
 
 	"github.com/hallelx2/llmgate"
+
 	"github.com/hallelx2/vectorless-engine/pkg/tree"
 )