Problem: Okular settings path was incomplete and didn't mention the
trigger keybinding.
Solution: Update to full path (Settings -> Configure Okular -> Editor)
and note that Shift+click triggers inverse search.
Problem: SyncTeX setup for forward/inverse search was undocumented,
forcing users to figure out viewer-specific CLI flags on their own.
Solution: Add `preview-synctex` vimdoc section with shared setup and
per-viewer recipes for Zathura, Sioyek, and Okular. Add FAQ entry
in README pointing to the new section.
Problem: the README and vimdoc presets list omitted `plantuml` and
`mermaid` after both were added.
Solution: add both presets to the vimdoc table and the README features
blurb.
Problem: The vimdoc used `preview.nvim.txt` filename and
`*preview.nvim-xyz*` tags, inconsistent with other plugins.
Solution: Rename to `preview.txt`, normalize tags to `*preview-xyz*`,
add contents/install sections, and use `{field} (type)` formatting.
