Add self-hosted RCS backend, extension, and ops tooling

Ship the Go/SQLite API and Web UI, Chrome/Brave capture addon,
Docker Compose, Pangolin reverse-proxy support, and a user-crontab
watchdog so the binary stays running without systemd.

extension/manifest.json

@@ -0,0 +1,50 @@
+{
+  "manifest_version": 3,
+  "name": "RCS — Reddit Comment Saver",
+  "version": "0.1.10",
+  "description": "Auto-saves Reddit comments and posts to your self-hosted RCS backend.",
+  "permissions": [
+    "storage",
+    "unlimitedStorage",
+    "activeTab",
+    "tabs"
+  ],
+  "host_permissions": [
+    "<all_urls>",
+    "https://www.reddit.com/*",
+    "https://old.reddit.com/*",
+    "https://reddit.com/*",
+    "http://127.0.0.1/*",
+    "http://localhost/*"
+  ],
+  "optional_host_permissions": [
+    "http://*/*",
+    "https://*/*"
+  ],
+  "background": {
+    "service_worker": "background/service-worker.js"
+  },
+  "action": {
+    "default_title": "RCS",
+    "default_popup": "popup/popup.html"
+  },
+  "options_ui": {
+    "page": "options/options.html",
+    "open_in_tab": false
+  },
+  "content_scripts": [
+    {
+      "matches": [
+        "https://www.reddit.com/*",
+        "https://old.reddit.com/*",
+        "https://reddit.com/*"
+      ],
+      "js": [
+        "lib/api.js",
+        "content/scrape.js",
+        "content/capture.js"
+      ],
+      "run_at": "document_idle"
+    }
+  ]
+}