Fixes #3430

- [x] Simplified code
- [x] Use postgres FTS search
- [x] Improve UX for filters
- [x]  Improve submission listing
- [x] Add filter for submission date, OTF have asked about this.
- [x] Add submission ID search, see
https://github.com/HyphaApp/hypha/pull/3294
- [x]   Make sure the batch actions are working 
- [x]   Permissions check for batch actions
- [x] Ensure search index works after submissions is updated
- [x] ~Integrate Django messages framework with htmx responses~ (Not
needed)
- [x] [Fix Polynomial regular expression used on uncontrolled
data](https://github.com/HyphaApp/hypha/security/code-scanning/74

)
- [ ] make bulk update status working, currently it's hidden.

---------

Co-authored-by: Fredrik Jonsson <frjo@xdeb.org>

Run Django and docs preview server, and watch and compile frontend
changes in parallel.

This lets you quickly spin up and run everything in a single terminal.

- Add page last edited info on each page
- Update header - site title, repo name & icon
- Disable custom fonts, use system-fonts
- Add copyright info in footer
- Update navigation structure and behaviour
- Add source code view and edit buttons
- Refractor documentation