docs: add full wiki with 74 pages, assets, and CI workflow

Adds the complete TREK documentation wiki covering installation,
trip planning, admin panel, MCP/AI integration, addons, and operations.

Also fixes encrypt-at-rest gaps: mapbox_access_token, Synology
credentials, per-user webhook/ntfy tokens, and photo passphrases
are now rotated by migrate-encryption.ts and stored encrypted via
settingsService.

wiki/Collab-Notes.md

@@ -0,0 +1,72 @@
+# Collab Notes
+
+Share structured, richly formatted notes with your group. Notes are organized into color-coded categories and can be pinned, attached with files, and linked to external websites.
+
+<!-- TODO: screenshot: collab notes editor with categories -->
+
+![Collab Notes](assets/Collab.png)
+
+## Where to find it
+
+Open the trip planner → **Collab** tab → **Notes** section. The Collab addon must be enabled and the Notes sub-feature must be turned on. See [Real-Time-Collaboration](Real-Time-Collaboration).
+
+## Categories
+
+Notes are grouped into categories. Each category has a name and a color chosen from six swatches: **Indigo**, **Red**, **Amber**, **Emerald**, **Blue**, and **Violet**.
+
+To manage categories, click the settings (gear) icon in the Notes header (only visible to users with the `collab_edit` permission). From the category settings modal you can:
+
+- Add a new category (type a name and click **+**)
+- Rename a category by clicking its name inline
+- Change a category's color by clicking a swatch
+- Delete a category
+
+All changes (including color updates) are staged locally and applied only when you click **Save** in the modal. Saving a color change updates every note in that category.
+
+## Creating a note
+
+Click **+ New Note** in the Notes header (only visible to users with the `collab_edit` permission). A modal opens with the following fields:
+
+| Field | Required | Notes |
+|-------|----------|-------|
+| Title | Yes | Plain text |
+| Body | No | Markdown |
+| Category | No | Select from existing categories |
+| Website | No | URL; shows an Open Graph thumbnail on the note card |
+| Attachments | No | Files up to 50 MB; see restrictions below |
+
+Click **Create** to save.
+
+## Markdown support
+
+Note bodies are rendered as GitHub Flavored Markdown with soft line breaks. Supported syntax includes headings, bold/italic, links, ordered and unordered lists, task lists, tables, fenced code blocks, and blockquotes.
+
+## Pinning
+
+Click the pin icon on a note card to pin it. Pinned notes sort to the top of the list (above all unpinned notes, regardless of category). Click again (shown as the unpin icon) to unpin.
+
+## Attachments
+
+You can attach images, PDFs, and other files to a note (requires the `file_upload` permission). Maximum file size is **50 MB** per file.
+
+The following file types are blocked: `.svg`, `.html`, `.htm`, `.xml`, `.xhtml`, `.js`, `.jsx`, `.ts`, `.exe`, `.bat`, `.sh`, `.cmd`, `.msi`, `.dll`, `.com`, `.vbs`, `.ps1`, `.php`.
+
+Image thumbnails are shown on the note card. Click a thumbnail to open a lightbox. PDFs open in a document viewer overlay.
+
+You can also paste images or PDFs directly into the create/edit form (if the `file_upload` permission is granted).
+
+## Editing a note
+
+Click the pencil icon on a note card to open the edit modal. All fields, including attachments, can be updated. To remove an existing attachment, click the **×** next to it in the edit form.
+
+## Expanding a note
+
+Click the expand icon (arrows) on a note card to open a full-content view in a portal overlay. Users with the `collab_edit` permission will see a pencil button in the overlay header to switch directly to the edit modal.
+
+## Filtering
+
+Use the category filter pills below the Notes header to show only notes belonging to a specific category. Click **All** to clear the filter.
+
+## Related pages
+
+[Real-Time-Collaboration](Real-Time-Collaboration) · [Collab-Chat](Collab-Chat) · [Collab-Polls](Collab-Polls)