feat: ejecutar tests desde el dashboard TUI

Se añade opción "Run Tests" al menú del servidor en el dashboard TUI.
Ejecuta `go test -tags goolm -count=1 ./...` y muestra los resultados
en una pantalla dedicada (ScreenTestOutput) con scroll y opción de re-ejecutar.

Cambios:
- pkg/tui: nuevo MsgTestsDone, ScreenTestOutput, IntentRunTests, updateTestOutput
- pkg/tui/view.go: viewTestOutput con scroll y controles (↑↓ r 0)
- shell/tui/adapter.go: runTests() ejecuta go test con el env del manager
- shell/process/manager.go: buildEnv → BuildEnv (exportado) para que el adapter
  pueda construir el env completo con las variables de .env

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

pkg/tui/update.go

@@ -21,6 +21,7 @@ const (
 	IntentRestartLauncher IntentKind = "restart_launcher"
 	IntentKillLauncher    IntentKind = "kill_launcher"
 	IntentRebuildRestart  IntentKind = "rebuild_restart"
+	IntentRunTests        IntentKind = "run_tests"
 )
 
 // Intent is pure data describing a side effect to execute.
@@ -98,6 +99,18 @@ func Update(model Model, msg interface{}) (Model, []Intent) {
 		model.LogScroll = max(0, len(m.Lines)-visibleLogLines(model))
 		return model, nil
 
+	case MsgTestsDone:
+		model.Screen = ScreenTestOutput
+		model.LogLines = m.Output
+		model.LogScroll = 0
+		model.Cursor = 0
+		if m.Passed {
+			model.StatusMsg = "Tests PASSED"
+		} else {
+			model.StatusMsg = "Tests FAILED"
+		}
+		return model, nil
+
 	case MsgTick:
 		return model, []Intent{{Kind: IntentLoadAgents}}
 
@@ -127,6 +140,8 @@ func updateKey(model Model, key KeyMsg) (Model, []Intent) {
 		return updateLogs(model, key)
 	case ScreenServer:
 		return updateServerScreen(model, key)
+	case ScreenTestOutput:
+		return updateTestOutput(model, key)
 	}
 	return model, nil
 }
@@ -283,6 +298,9 @@ func executeServerAction(model Model, action string) (Model, []Intent) {
 	case "Rebuild & Restart":
 		model.StatusMsg = "Building & restarting..."
 		return model, []Intent{{Kind: IntentRebuildRestart}}
+	case "Run Tests":
+		model.StatusMsg = "Running tests..."
+		return model, []Intent{{Kind: IntentRunTests}}
 	case "Logs":
 		model.Screen = ScreenLogs
 		model.LogLines = nil
@@ -294,6 +312,26 @@ func executeServerAction(model Model, action string) (Model, []Intent) {
 	return model, nil
 }
 
+func updateTestOutput(model Model, key KeyMsg) (Model, []Intent) {
+	switch key.Str {
+	case "0":
+		model.Screen = ScreenServer
+		model.Cursor = 0
+		model.LogLines = nil
+		model.LogScroll = 0
+		model.StatusMsg = ""
+	case "up", "k":
+		model.LogScroll = max(0, model.LogScroll-1)
+	case "down", "j":
+		maxScroll := max(0, len(model.LogLines)-visibleLogLines(model))
+		model.LogScroll = min(model.LogScroll+1, maxScroll)
+	case "r":
+		model.StatusMsg = "Running tests..."
+		return model, []Intent{{Kind: IntentRunTests}}
+	}
+	return model, nil
+}
+
 // ── pure helpers ─────────────────────────────────────────────────────────
 
 func visibleLogLines(m Model) int {