Add backups with S3, daily cost push, automation templates and a browser tool

- Daily backups (database + config) into <data_dir>/backups, keep N,
  optional upload to any S3-compatible bucket (SigV4, bucket pruning);
  settings panel with run-now, list and download
- Daily cost summary push at 20:00 (opt-in per user, preview button)
- Automations from templates (dependency check, security review, test
  health, daily summary, TODO report, docs freshness) via POST /jobs/create
- browser tool: headless Chromium over CDP – click, type, keys, waits,
  JavaScript, navigation, screenshots, console errors; requests to private
  network addresses are blocked (sub-resources and redirects included)
- Secrets masked in the config view: S3 secret key, metrics token
- Replace the remaining text arrows/refresh glyphs with SVG icons

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/Cargo.toml

@@ -32,6 +32,7 @@ serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 similar = "2"
 tokio = { version = "1", features = ["full"] }
+tokio-tungstenite = "0.29"
 tokio-util = "0.7"
 toml = "1"
 toml_edit = "0.25"