refactor: move CLI entry point to pkg/cli, remove cmd/

Consolidate CLI code into pkg/cli:
- Add pkg/cli/app.go with Main() entry point and completionCmd
- Move build variants to internal/variants/ (avoids import cycle)
- Move i18n-validate tool to internal/tools/
- Update main.go to call cli.Main()
- Remove cmd/ directory entirely

Structure:
- main.go imports internal/variants (triggers command registration)
- main.go calls cli.Main() which runs the CLI
- Build variants: go build, go build -tags ci/php/minimal

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Taskfile.yml

@@ -1,12 +1,18 @@
 version: '3'
 
-includes:
-  gui: ./cmd/lthn-desktop/Taskfile.yml
-  cli: ./cmd/core/Taskfile.yml
-  demo: ./cmd/core-demo/Taskfile.yml
-  ide: ./cmd/core-gui/Taskfile.yml
-
 tasks:
+  cli:build:
+    desc: "Build the core CLI executable"
+    cmds:
+      - go build -o ./bin/core .
+
+  cli:run:
+    desc: "Build and run the core CLI"
+    cmds:
+      - task: cli:build
+      - ./bin/core {{.CLI_ARGS}}
+
+
   test:
     desc: "Run all Go tests recursively for the entire project."
     cmds:
@@ -53,4 +59,4 @@ tasks:
   i18n:validate:
     desc: "Validate i18n key usage across the codebase"
     cmds:
-      - go run ./cmd/i18n-validate ./...
+      - go run ./internal/tools/i18n-validate ./...

cmd/Taskfile.yml

@@ -1,13 +0,0 @@
-version: '3'
-
-tasks:
-  build:
-    summary: Builds the core executable
-    cmds:
-      - go build -o {{.TASKFILE_DIR}}/../bin/core {{.TASKFILE_DIR}}/..
-
-  build:dev:
-    summary: Builds and runs the core executable in development mode
-    cmds:
-      - go build -o {{.TASKFILE_DIR}}/../bin/core {{.TASKFILE_DIR}}/..
-      - CORE_DEV_TOOLS="false" {{.TASKFILE_DIR}}/../bin/core

main.go

@@ -4,11 +4,15 @@ import (
 	"fmt"
 	"os"
 
-	"github.com/host-uk/core/cmd"
+	"github.com/host-uk/core/pkg/cli"
+
+	// Build variants import commands via self-registration.
+	// See internal/variants/ for available variants: full, ci, php, minimal.
+	_ "github.com/host-uk/core/internal/variants"
 )
 
 func main() {
-	if err := cmd.Execute(); err != nil {
+	if err := cli.Main(); err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}

pkg/cli/app.go

@@ -1,65 +1,44 @@
-// Package cmd implements the core CLI application.
-//
-// The CLI provides commands for:
-//   - Multi-repo development workflows (dev)
-//   - AI agent task management (ai)
-//   - Go and PHP development tools (go, php)
-//   - Build and release automation (build, ci)
-//   - SDK validation and API compatibility (sdk)
-//   - Package and environment management (pkg, vm)
-//   - Documentation and testing (docs, test)
-//   - Environment health checks (doctor)
-//   - Repository setup and cloning (setup)
-//
-// Two build variants exist:
-//   - Default build: Full development toolset
-//   - CI build (-tags ci): Minimal release toolset
-package cmd
+package cli
 
 import (
 	"os"
 
-	"github.com/host-uk/core/pkg/cli"
 	"github.com/host-uk/core/pkg/framework"
+	"github.com/host-uk/core/pkg/log"
 	"github.com/spf13/cobra"
-
-	// Build variants import commands via self-registration.
-	// See cmd/variants/ for available variants: full, ci, php, minimal.
-	_ "github.com/host-uk/core/cmd/variants"
 )
 
 const (
-	appName    = "core"
-	appVersion = "0.1.0"
+	// AppName is the CLI application name.
+	AppName = "core"
+	// AppVersion is the CLI application version.
+	AppVersion = "0.1.0"
 )
 
-
-
-// Execute initialises and runs the CLI application.
-// Commands are registered based on build tags (see core_ci.go and core_dev.go).
-func Execute() error {
+// Main initialises and runs the CLI application.
+// This is the main entry point for the CLI.
+func Main() error {
 	// Initialise CLI runtime with services
-	if err := cli.Init(cli.Options{
-		AppName: appName,
-		Version: appVersion,
+	if err := Init(Options{
+		AppName: AppName,
+		Version: AppVersion,
 		Services: []framework.Option{
-			framework.WithName("i18n", cli.NewI18nService(cli.I18nOptions{})),
-			framework.WithName("log", cli.NewLogService(cli.LogOptions{
-				Level: cli.LogLevelInfo,
+			framework.WithName("i18n", NewI18nService(I18nOptions{})),
+			framework.WithName("log", NewLogService(log.Options{
+				Level: log.LevelInfo,
 			})),
 		},
 	}); err != nil {
 		return err
 	}
-	defer cli.Shutdown()
+	defer Shutdown()
 
 	// Add completion command to the CLI's root
-	cli.RootCmd().AddCommand(completionCmd)
+	RootCmd().AddCommand(completionCmd)
 
-	return cli.Execute()
+	return Execute()
 }
 
-
 // completionCmd generates shell completion scripts.
 var completionCmd = &cobra.Command{
 	Use:   "completion [bash|zsh|fish|powershell]",