feat: allow direct pdf archives

[fmartingr]

This pull request aims to provide PDF archives for bookmarks by directly downloading the file.

Notable changes

• Logic for archivers now uses the ArchiverDomain
  • ArchiverDomain initializes a list of archivers that try to match the content type, if it does, that archiver is used. If an error is raised, the next archiver is used and so on.
• Added PDFArchiver: Just downloads the file.
• Added WARCArchiver as a "catch all" (current default)
• Added database columns bookmark.archiver (warc/pdf) and archive_path.
  • Bookmark has an archive if archive_path != ""

Pending

• [ ] Migrate the archive_path for existing bookmarks: iterate over the bookmarks, check if the archive exists and set the path and the archiver to warc.
• [ ] Refactor EPub logic separate from the archiver
• [x] Allow different archivers in archive page

Closes #929

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 36.41026% with 124 lines in your changes missing coverage. Please review.

Project coverage is 35.20%. Comparing base (4a5564d) to head (9d34bad).

:exclamation: Current head 9d34bad differs from pull request most recent head 8c1ed87

Please upload reports for the commit 8c1ed87 to get more accurate results.

Files	Patch %	Lines
internal/http/routes/bookmark.go	11.11%	32 Missing :warning:
internal/webserver/handler-api-ext.go	0.00%	24 Missing :warning:
internal/domains/archiver.go	0.00%	15 Missing :warning:
internal/domains/storage.go	0.00%	13 Missing :warning:
internal/webserver/handler-api.go	0.00%	10 Missing :warning:
internal/cmd/add.go	0.00%	9 Missing :warning:
internal/database/mysql.go	71.42%	4 Missing and 4 partials :warning:
internal/archiver/pdf.go	41.66%	7 Missing :warning:
internal/http/routes/api/v1/bookmarks.go	0.00%	4 Missing :warning:
internal/archiver/warc.go	87.50%	1 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #942 +/- ## ========================================== + Coverage 35.17% 35.20% +0.02% ========================================== Files 61 63 +2 Lines 4065 4116 +51 ========================================== + Hits 1430 1449 +19 - Misses 2413 2443 +30 - Partials 222 224 +2 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.