feat: public platform, admin console, templates, landing docs

Projects become publicly browsable after admin approval; management and
secret-adjacent reads (logs, variables, exec, connection URLs) require
owner/member/admin auth, and platform controls sit behind RequireAdmin.

- Backend: OptionalAuth middleware, read/authed/admin route groups,
  projects.is_approved + service_templates.owner_id migration,
  visibility-aware sqlc queries, admin overview/users/approval endpoints,
  EnsureAdminAccount bootstrap (ADMIN_* env), 30 seeded templates with
  owner CRUD, managed-database connection URLs gated owner+admin, fix
  DB.Stats() infinite recursion.
- Frontend: expandable persisted sidebar + clickable user menu, public
  landing page with searchable docs browser (GitHub sync, bundled
  snapshot + localStorage fallback), DocsBrowser shared with /docs,
  template create/edit/JSON-upload for owned templates, database create
  dialog, admin console (stats, approvals, project edit/delete, user
  admin toggles), HA/Security/Usage polish with dead CSS tokens mapped
  to real theme vars, anonymous-safe gating on every mutation control.
- Tests: safe window.localStorage access fixes happy-dom crashes in
  PlatformShell and canvas storage.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/frontend/package-lock.json

@@ -32,6 +32,7 @@
         "@tailwindcss/postcss": "^4.1.18",
         "@tailwindcss/typography": "^0.5.19",
         "@tanstack/react-query": "^5.66.0",
+        "@types/dompurify": "^3.0.5",
         "@xyflow/react": "^12.10.0",
         "autoprefixer": "^10.4.24",
         "axios": "^1.7.9",
@@ -40,7 +41,9 @@
         "clsx": "^2.1.1",
         "cmdk": "^1.1.1",
         "date-fns": "^4.1.0",
+        "dompurify": "^3.2.6",
         "lucide-react": "^0.563.0",
+        "marked": "^18.0.13",
         "postcss": "^8.5.6",
         "react": "^19.2.0",
         "react-dom": "^19.2.0",
@@ -3719,6 +3722,15 @@
       "devOptional": true,
       "license": "MIT"
     },
+    "node_modules/@types/dompurify": {
+      "version": "3.0.5",
+      "resolved": "https://registry.npmjs.org/@types/dompurify/-/dompurify-3.0.5.tgz",
+      "integrity": "sha512-1Wg0g3BtQF7sSb27fJQAKck1HECM6zV1EB66j8JH9i3LCjYabJa0FSdiSgsD5K/RbrsR0SiraKacLB+T8ZVYAg==",
+      "license": "MIT",
+      "dependencies": {
+        "@types/trusted-types": "*"
+      }
+    },
     "node_modules/@types/estree": {
       "version": "1.0.8",
       "resolved": "https://registry.npmjs.org/@types/estree/-/estree-1.0.8.tgz",
@@ -3763,6 +3775,12 @@
         "@types/react": "^19.2.0"
       }
     },
+    "node_modules/@types/trusted-types": {
+      "version": "2.0.7",
+      "resolved": "https://registry.npmjs.org/@types/trusted-types/-/trusted-types-2.0.7.tgz",
+      "integrity": "sha512-ScaPdn1dQczgbl0QFTeTOmVHFULt394XJgOQNoyVhZ6r2vLnMLJfBPd53SB52T/3G36VI1/g2MZaX0cwDuXsfw==",
+      "license": "MIT"
+    },
     "node_modules/@types/use-sync-external-store": {
       "version": "0.0.6",
       "resolved": "https://registry.npmjs.org/@types/use-sync-external-store/-/use-sync-external-store-0.0.6.tgz",
@@ -5205,6 +5223,15 @@
       "license": "MIT",
       "peer": true
     },
+    "node_modules/dompurify": {
+      "version": "3.2.6",
+      "resolved": "https://registry.npmjs.org/dompurify/-/dompurify-3.2.6.tgz",
+      "integrity": "sha512-/2GogDQlohXPZe6D6NOgQvXLPSYBqIWMnZ8zzOhn09REE4eyAzb+Hed3jhoM9OkuaJ8P6ZGTTVWQKAi8ieIzfQ==",
+      "license": "(MPL-2.0 OR Apache-2.0)",
+      "optionalDependencies": {
+        "@types/trusted-types": "^2.0.7"
+      }
+    },
     "node_modules/dunder-proto": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/dunder-proto/-/dunder-proto-1.0.1.tgz",
@@ -6577,6 +6604,18 @@
         "node": ">=10"
       }
     },
+    "node_modules/marked": {
+      "version": "18.0.13",
+      "resolved": "https://registry.npmjs.org/marked/-/marked-18.0.13.tgz",
+      "integrity": "sha512-xTxVzZsBFwunP6HDmtBkabUQEYArnP7/rMDGmPj9SlrKlQ4i8MdYVow+nJL0eOqwpUqhzBoTBRADGN6uYwPyOw==",
+      "license": "MIT",
+      "bin": {
+        "marked": "bin/marked.js"
+      },
+      "engines": {
+        "node": ">= 20"
+      }
+    },
     "node_modules/math-intrinsics": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/math-intrinsics/-/math-intrinsics-1.1.0.tgz",