feat: implement core CLI packages and Phase 3 commands

- config: resolve binary dir, load/save .hf-config.json
- mode: detect padded-cell vs manual mode via pass_mgr
- client: HTTP client wrapper with auth header support
- passmgr: pass_mgr integration (get-secret, set, generate)
- output: human-readable + JSON output formatting with tables
- help: help and help-brief renderer for groups/commands
- commands: version, health, config (--url, --acc-mgr-token, show)
- auth: token resolution helper (padded-cell auto / manual explicit)
- main: command dispatcher with --json global flag support
- README: updated with current package layout and status

internal/commands/version.go

@@ -0,0 +1,19 @@
+package commands
+
+import (
+	"fmt"
+
+	"git.hangman-lab.top/zhi/HarborForge.Cli/internal/output"
+)
+
+// Version is the CLI version string, set at build time via ldflags.
+var Version = "dev"
+
+// RunVersion prints the CLI version.
+func RunVersion() {
+	if output.JSONMode {
+		output.PrintJSON(map[string]string{"version": Version})
+	} else {
+		fmt.Printf("hf %s\n", Version)
+	}
+}