feat(skills): detect installed AI agents and install the DeployHQ skill

internal/commands/hello.go

@@ -58,7 +58,12 @@ func newHelloCmd() *cobra.Command {
 				env.Status("Logged in as %s on %s.%s", creds.Email, creds.Account, host)
 			}
 
-			// Step 2: Fetch projects
+			// Step 2: Offer to install the DeployHQ skill for any AI agents
+			// installed on this machine. Auto-installs for the runtime agent,
+			// prompts for others. Non-fatal — hello continues on errors.
+			offerSkillInstall(env)
+
+			// Step 3: Fetch projects
 			var sdkOpts []sdk.Option
 			if baseURL := cliCtx.Config.BaseURL(creds.Account); baseURL != "" {
 				sdkOpts = append(sdkOpts, sdk.WithBaseURL(baseURL))
@@ -101,7 +106,7 @@ func newHelloCmd() *cobra.Command {
 				return initCmd.RunE(initCmd, nil)
 			}
 
-			// Step 3: Default project
+			// Step 4: Default project
 			defaultProject := cliCtx.Config.Project
 			if defaultProject != "" {
 				env.Status("Default project: %s", defaultProject)
@@ -134,7 +139,7 @@ func newHelloCmd() *cobra.Command {
 				output.ColorGreen.Fprintf(env.Stderr, "Saved to %s\n", path) //nolint:errcheck
 			}
 
-			// Step 4: Orientation
+			// Step 5: Orientation
 			env.Status("")
 			env.Status("You're all set! Here are some useful commands:")
 			env.Status("  dhq deploy            Deploy your project")

internal/commands/hello_skills.go

@@ -0,0 +1,117 @@
+package commands
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/deployhq/deployhq-cli/internal/harness"
+	"github.com/deployhq/deployhq-cli/internal/output"
+	"github.com/deployhq/deployhq-cli/internal/skillinstaller"
+	"github.com/manifoldco/promptui"
+)
+
+// Test seams for offerSkillInstall. These three vars are the only external
+// state the function depends on; overriding them lets tests exercise every
+// branch (no targets / runtime auto-install / prompt yes / prompt no /
+// project-scope skip) without a live TTY or real agent installs.
+//
+// Production code MUST NOT reassign these — only the test files do.
+var (
+	detectInstalledFn    = skillinstaller.DetectInstalled
+	detectRuntimeAgentFn = harness.Detect
+	confirmInstallFn     = defaultConfirmInstall
+)
+
+// defaultConfirmInstall runs the Y/n promptui prompt and returns true on
+// "yes". Extracted from offerSkillInstall so tests can substitute a
+// deterministic answer.
+func defaultConfirmInstall(label string) bool {
+	prompt := promptui.Prompt{
+		Label:     label,
+		IsConfirm: true,
+		Default:   "Y",
+	}
+	_, err := prompt.Run()
+	return err == nil
+}
+
+// offerSkillInstall is the Wrangler-style post-login hook that detects locally
+// installed AI agents and offers to install the DeployHQ skill for them.
+//
+// Behaviour:
+//   - Runtime agent (the one currently running dhq, per harness.Detect) is
+//     auto-installed without prompting when an install is Needed — if the
+//     user is using dhq from inside Claude Code right now, they want it.
+//   - Other agents detected on disk are batched into a single Y/n prompt.
+//   - Errors are non-fatal: hello succeeds even if installs fail; users can
+//     re-run `dhq skills install` later.
+//
+// The function is a no-op when nothing is detected, when nothing needs
+// installing, or when env.NonInteractive is set.
+func offerSkillInstall(env *output.Envelope) {
+	detected := detectInstalledFn()
+	if len(detected) == 0 {
+		return
+	}
+
+	runtimeName := detectRuntimeAgentFn().Name
+
+	var runtime *skillinstaller.DetectResult
+	var others []skillinstaller.DetectResult
+	for i, d := range detected {
+		if !skillinstaller.Needed(d.Status) {
+			continue
+		}
+		// Project-scope targets (e.g. Copilot's .github/copilot-instructions.md)
+		// modify the current repo. Never install those as a side effect of
+		// 'dhq hello' — they're opt-in via 'dhq skills install --agent <name>'.
+		if d.Target.Scope() != skillinstaller.ScopeUser {
+			continue
+		}
+		if d.Target.Name() == runtimeName {
+			runtime = &detected[i]
+			continue
+		}
+		others = append(others, d)
+	}
+
+	if runtime != nil {
+		installOne(env, runtime.Target, "Installing DeployHQ skill for %s (you're using it now)…")
+	}
+
+	if len(others) == 0 || env.NonInteractive {
+		return
+	}
+
+	names := make([]string, len(others))
+	for i, d := range others {
+		names[i] = d.Target.DisplayName()
+	}
+	label := fmt.Sprintf("Detected AI agents that could use the DeployHQ skill: %s.\n  Install for them now?", strings.Join(names, ", "))
+
+	if !confirmInstallFn(label) {
+		env.Status("Skipping. Run `dhq skills install` later if you change your mind.")
+		return
+	}
+
+	for _, d := range others {
+		installOne(env, d.Target, "Installing DeployHQ skill for %s…")
+	}
+}
+
+// installOne runs Install on a single target and prints a result line.
+// statusFmt receives the DisplayName via %s.
+func installOne(env *output.Envelope, t skillinstaller.Target, statusFmt string) {
+	env.Status(statusFmt, t.DisplayName())
+	path, err := t.Install()
+	if err != nil {
+		env.Warn("Could not install %s skill: %v", t.DisplayName(), err)
+		return
+	}
+	output.ColorGreen.Fprintf(env.Stderr, "  Installed %s skill → %s\n", t.DisplayName(), path) //nolint:errcheck
+	if n, ok := t.(skillinstaller.Noter); ok {
+		if note := n.PostInstallNote(); note != "" {
+			env.Status("  %s", note)
+		}
+	}
+}