Update Mastodon to version 2.3.0

[Fraenkiman]

• Added limits for paging, deletion, and media uploads based on the Mastodon REST API documentation.

• There are now dynamic time windows for text-heavy, mixed, and media-heavy blogs. This results in the following behavior:

Synchronization from date: Manual permanent lower limit

    Automatic window for scheduled runs:
        7 / 14 / 30 days

    Synchronize modified older content anyway:
        Yes, via dirty queue

    Check old threads for replies:
        Optional, on a rotating basis

Starting with version 2.3.0, the plugin enforces the following limits for daily scheduled synchronization:

240 requests instead of 300
24 media uploads instead of 30
24 deletions instead of 30
10 requests remaining buffer

During a scheduled run, content sync and delete sync are technically separate processes, each with its own 240-request budget.

| Direction                     | Object type                                          |                                   Maximum value under ideal conditions |
| ----------------------------- | ---------------------------------------------------- | ---------------------------------------------------------------------: |
| FlatPress → Mastodon          | new/edited posts without media                       |                                                                    238 |
| FlatPress → Mastodon          | new/modified comments                                |                                  238 minus required post/context costs |
| FlatPress → Mastodon          | Posts with 1 media file                              |                                              24 posts containing media |
| FlatPress → Mastodon          | Posts with 4 media files                             |                                               6 posts containing media |
| Mastodon → FlatPress          | New top-level statuses during normal daily operations|                                                                     40 |
| Mastodon → FlatPress          | New top-level statuses during initial/backfill run   |                                                                    200 |
| Mastodon → FlatPress          | Replies/comments                                     | Theoretically very high via API, practically limited by runtime/memory |
| FlatPress → Mastodon Deletion | Deleted posts/comments                               |                                                    24 remote deletions |
| Mastodon → FlatPress Deletion | Detect remotely deleted statuses/replies             |                             up to 240 checks, excluding self-deletions |

Maximum new/updated Mastodon statuses or replies
= 238 - new_remote_statuses - known_context_checks - instance_info_request - media_uploads - media_polling