Remove --force from integration install, ensure shared infra on install/switch

- Remove --force parameter entirely from integration install; users must
  uninstall before reinstalling to prevent orphaned files
- Auto-install shared infrastructure (.specify/scripts/, .specify/templates/)
  when missing during install or switch
- Add test for shared infra creation on bare project install

Author: mnriem

src/specify_cli/__init__.py

@@ -1608,7 +1608,6 @@ def integration_install(
     key: str = typer.Argument(help="Integration key to install (e.g. claude, copilot)"),
     script: str = typer.Option(None, "--script", help="Script type: sh or ps (default: from init-options.json or platform default)"),
     integration_options: str = typer.Option(None, "--integration-options", help='Options for the integration (e.g. --integration-options="--commands-dir .myagent/cmds")'),
-    force: bool = typer.Option(False, "--force", help="Overwrite existing integration without uninstalling first"),
 ):
     """Install an integration into an existing project."""
     from .integrations import INTEGRATION_REGISTRY, get_integration
@@ -1632,23 +1631,24 @@ def integration_install(
     current = _read_integration_json(project_root)
     installed_key = current.get("integration")
 
-    if installed_key and installed_key == key and not force:
+    if installed_key and installed_key == key:
         console.print(f"[yellow]Integration '{key}' is already installed.[/yellow]")
-        console.print("Use [cyan]--force[/cyan] to reinstall, or [cyan]specify integration switch <target>[/cyan] to change.")
+        console.print("Run [cyan]specify integration uninstall[/cyan] first, then reinstall.")
         raise typer.Exit(0)
 
     if installed_key and installed_key != key:
         console.print(f"[red]Error:[/red] Integration '{installed_key}' is already installed.")
-        console.print(f"Use [cyan]specify integration switch {key}[/cyan] to switch integrations.")
-        if force:
-            console.print(
-                "[yellow]--force only supports reinstalling the currently installed integration "
-                "and cannot overwrite a different integration.[/yellow]"
-            )
+        console.print(f"Run [cyan]specify integration uninstall[/cyan] first, or use [cyan]specify integration switch {key}[/cyan].")
         raise typer.Exit(1)
 
     selected_script = _resolve_script_type(project_root, script)
 
+    # Ensure shared infrastructure exists
+    if not (project_root / ".specify" / "scripts").exists():
+        _install_shared_infra(project_root, selected_script)
+        if os.name != "nt":
+            ensure_executable_scripts(project_root)
+
     manifest = IntegrationManifest(
         integration.key, project_root, version=get_speckit_version()
     )
@@ -1862,6 +1862,12 @@ def integration_switch(
         opts.pop("ai_skills", None)
         save_init_options(project_root, opts)
 
+    # Ensure shared infrastructure exists
+    if not (project_root / ".specify" / "scripts").exists():
+        _install_shared_infra(project_root, selected_script)
+        if os.name != "nt":
+            ensure_executable_scripts(project_root)
+
     # Phase 2: Install target integration
     console.print(f"Installing integration: [cyan]{target}[/cyan]")
     manifest = IntegrationManifest(

tests/integrations/test_integration_subcommand.py

@@ -106,6 +106,7 @@ def test_install_already_installed(self, tmp_path):
             os.chdir(old_cwd)
         assert result.exit_code == 0
         assert "already installed" in result.output
+        assert "uninstall" in result.output
 
     def test_install_different_when_one_exists(self, tmp_path):
         project = _init_project(tmp_path, "copilot")
@@ -117,22 +118,7 @@ def test_install_different_when_one_exists(self, tmp_path):
             os.chdir(old_cwd)
         assert result.exit_code != 0
         assert "already installed" in result.output
-
-    def test_force_blocked_with_different_integration(self, tmp_path):
-        """--force must not allow overwriting a different integration."""
-        project = _init_project(tmp_path, "copilot")
-        old_cwd = os.getcwd()
-        try:
-            os.chdir(project)
-            result = runner.invoke(app, [
-                "integration", "install", "claude", "--force",
-                "--script", "sh",
-            ])
-        finally:
-            os.chdir(old_cwd)
-        assert result.exit_code != 0
-        assert "already installed" in result.output
-        assert "cannot overwrite a different integration" in result.output
+        assert "uninstall" in result.output
 
     def test_install_into_bare_project(self, tmp_path):
         """Install into a project with .specify/ but no integration."""
@@ -161,6 +147,26 @@ def test_install_into_bare_project(self, tmp_path):
         # Claude uses skills directory (not commands)
         assert (project / ".claude" / "skills" / "speckit-plan" / "SKILL.md").exists()
 
+    def test_install_bare_project_gets_shared_infra(self, tmp_path):
+        """Installing into a bare project should create shared scripts and templates."""
+        project = tmp_path / "bare"
+        project.mkdir()
+        (project / ".specify").mkdir()
+        old_cwd = os.getcwd()
+        try:
+            os.chdir(project)
+            result = runner.invoke(app, [
+                "integration", "install", "claude",
+                "--script", "sh",
+            ], catch_exceptions=False)
+        finally:
+            os.chdir(old_cwd)
+        assert result.exit_code == 0, result.output
+
+        # Shared infrastructure should be present
+        assert (project / ".specify" / "scripts").is_dir()
+        assert (project / ".specify" / "templates").is_dir()
+
 
 # ── uninstall ────────────────────────────────────────────────────────