docs: bootstrap user-facing documentation from codebase audit

- Add 5 new Tier 1 doc pages: configuration, stack-management, editor,
  multi-node, and alerts-notifications
- Update introduction, quickstart, and features/overview to reflect
  current feature set and link to new pages
- Restructure mint.json with Getting Started / Features / Reference /
  Operations navigation groups
- Add Playwright-captured screenshots for all major UI screens

docs/features/editor.mdx

@@ -0,0 +1,64 @@
+---
+title: Editor
+description: Edit compose files and environment variables, and manage containers directly from the dashboard.
+---
+
+Selecting a stack opens the editor view — a split-pane layout with container management on the left and a full Monaco code editor on the right.
+
+<Frame>
+  <img src="/images/editor/editor-overview.png" alt="Editor view showing container panel and Monaco editor" />
+</Frame>
+
+## Compose file editor
+
+The right panel shows your `compose.yaml` with full syntax highlighting. By default the editor is **read-only** to prevent accidental changes.
+
+Click **Edit** to enter edit mode. Your changes are unsaved until you explicitly save them.
+
+### Save options
+
+| Button | What it does |
+|--------|--------------|
+| **Save** | Writes the file to disk. Does not restart any containers. |
+| **Save & Deploy** | Writes the file, then immediately runs `docker compose up -d`. Use this to apply compose changes in one step. |
+| **Discard** | Reverts the editor to the last saved version. Unsaved changes are lost. |
+
+## Environment file editor
+
+Click the **.env** tab to switch to the environment file editor. If your `compose.yaml` references multiple env files (via `env_file:`), a dropdown lets you select which file to edit.
+
+The `.env` editor has the same save/discard controls as the compose editor. Changes take effect the next time the stack is deployed.
+
+<Note>
+  Sencho reads the `env_file:` paths from your `compose.yaml` to discover available env files. If no `env_file:` is declared, a default `.env` in the stack directory is used.
+</Note>
+
+## Container panel
+
+The left panel lists all containers that belong to the selected stack. Each container shows:
+
+- **Status badge** — `running`, `exited`, `starting`, or `unhealthy`
+- **Live stats** — CPU %, RAM usage, and network I/O updated every 1–2 seconds
+- **Port mappings** — host:container port pairs (if any)
+
+### Container actions
+
+Each container row has three action buttons:
+
+| Button | What it does |
+|--------|--------------|
+| **Logs** (external link icon) | Opens a live log stream modal for that container |
+| **Terminal** (terminal icon) | Opens an interactive bash session inside the container |
+| **Copy ID** | Copies the container ID to the clipboard |
+
+### Log viewer
+
+The log viewer streams output from a single container in real-time using Server-Sent Events. Logs auto-scroll to the bottom as new lines arrive. Close the modal to stop the stream.
+
+### Container terminal (exec)
+
+The terminal modal gives you an interactive bash shell inside the running container — equivalent to `docker exec -it <id> bash`. It uses a full xterm.js emulator with color support and tab completion.
+
+<Warning>
+  The container terminal requires the container to have `bash` (or `sh`) installed. Minimal images (e.g. Alpine-based) may need `sh` instead.
+</Warning>