Add installed_plugins.json template and fix gitignore

- Add !*.tmpl exception to allow chezmoi templates
- installed_plugins.json.tmpl uses home dir variable for portability

.gitignore

@@ -1,2 +1,3 @@
 *tmp*
+!*.tmpl
 .ropeproject

dot_claude/plugins/installed_plugins.json.tmpl

@@ -0,0 +1,35 @@
+{
+  "version": 2,
+  "plugins": {
+    "code-simplifier@claude-plugins-official": [
+      {
+        "scope": "user",
+        "installPath": "{{ .chezmoi.homeDir }}/.claude/plugins/cache/claude-plugins-official/code-simplifier/1.0.0",
+        "version": "1.0.0",
+        "installedAt": "2026-01-25T12:07:24.781Z",
+        "lastUpdated": "2026-01-25T12:07:24.781Z",
+        "gitCommitSha": "96276205880a60fd66bbae981f5ab568e70c4cbf"
+      }
+    ],
+    "ralph-loop@claude-plugins-official": [
+      {
+        "scope": "user",
+        "installPath": "{{ .chezmoi.homeDir }}/.claude/plugins/cache/claude-plugins-official/ralph-loop/96276205880a",
+        "version": "96276205880a",
+        "installedAt": "2026-01-25T12:07:24.835Z",
+        "lastUpdated": "2026-01-25T12:07:24.835Z",
+        "gitCommitSha": "96276205880a60fd66bbae981f5ab568e70c4cbf"
+      }
+    ],
+    "superpowers@claude-plugins-official": [
+      {
+        "scope": "user",
+        "installPath": "{{ .chezmoi.homeDir }}/.claude/plugins/cache/claude-plugins-official/superpowers/4.1.1",
+        "version": "4.1.1",
+        "installedAt": "2026-02-03T19:32:32.707Z",
+        "lastUpdated": "2026-02-03T19:32:32.707Z",
+        "gitCommitSha": "06b92f36820f38175b2ed6ff3f8df45157d54731"
+      }
+    ]
+  }
+}