docs: add FeedFlow and FluentFlame Reader to APIs & native apps (#8820)

Adds two requested clients to the APIs & native apps tables: FeedFlow (mobile, table 1) and FluentFlame Reader (desktop, table 2).

Both rows go at the bottom of their tables to avoid implying a recommendation order, since [an earlier comment](https://github.com/FreshRSS/FreshRSS/pull/8787#issuecomment-4373379000) noted the top reflects recommended apps.

Columns come from each project's README. Cells not documented upstream are left as `❔`, same as Vienna RSS, lire, and Fiery Feeds.

FluentFlame Reader is marked `Work in progress` because its [README](https://github.com/FluentFlame/fluentflame-reader#download) states "Currently we do not have any stable version!". Same handling as the Netnewswire row.

FeedFlow's sync-spam issue was fixed upstream in [feed-flow#425](https://github.com/prof18/feed-flow/issues/425), closed 2025-02-06 with commit [`a6b6e4c`](https://github.com/prof18/feed-flow/commit/a6b6e4ce760408d8902ca780e4ee59c3d0c03afc). 15 months and 14 releases since, no re-report.

Potentially closes #7301, #8608

Co-authored-by: Bjørn A. Andersen <polybjorn@users.noreply.github.com>

README.md

@@ -168,6 +168,7 @@ and [Fever API](https://freshrss.github.io/FreshRSS/en/developers/06_Fever_API.h
 | [Read You](https://github.com/Ashinch/ReadYou/)                                       | Android     | [✔️](https://github.com/Ashinch/ReadYou/)                     | ✔️✔️                   | GReader          | ✔️            | ⭐⭐       | ✔️                             | ✔️                  | ✔️         | ➖     | ➖       | ✔️           |
 | [Your News](https://yournews.app/)                                                    | Android, iOS| ➖                                                            | ✔️✔️                   | GReader          | ➖️            | ⭐        | ✔️                             | ✔️                  | ✔️        | ➖     | ➖      | ➖        |
 | [Fluent Reader Lite](https://hyliu.me/fluent-reader-lite/)                            | Android, iOS| [✔️](https://github.com/yang991178/fluent-reader-lite)        | ✔️                     | GReader          | ✔️            | ⭐⭐       | ➖                             | ➖                  | ✓         | ➖     | ➖       | ➖           |
+| [FeedFlow](https://www.feedflow.dev)                                                  | Android, iOS, Linux, macOS, Windows | [✔️](https://github.com/prof18/feed-flow)                     | ✔️✔️                   | GReader          | ✔️            | ❔        | ❔                             | ❔                  | ✔️         | ❔     | ➖       | ✔️           |
 
 | App                                                                                   | Platform    | Free Software                                                 | Maintained & Developed | API              | Works offline | Fast sync | Fetch more in individual views | Fetch read articles | Favourites | Labels | Podcasts | Manage feeds |
 |:--------------------------------------------------------------------------------------|:-----------:|:-------------------------------------------------------------:|:----------------------:|:----------------:|:-------------:|:---------:|:------------------------------:|:-------------------:|:----------:|:------:|:--------:|:------------:|
@@ -175,6 +176,7 @@ and [Fever API](https://freshrss.github.io/FreshRSS/en/developers/06_Fever_API.h
 | [RSS Guard](https://github.com/martinrotter/rssguard)             | Windows, GNU/Linux, macOS, OS/2 | [✔️](https://github.com/martinrotter/rssguard)                | ✔️✔️                   | GReader          | ✔️            | ⭐⭐      | ➖ | ✔️ | ✔️ | ✔️ | ✔️ | ✔️ |
 | [NewsFlash](https://gitlab.com/news-flash/news_flash_gtk)                             | GNU/Linux   | [✔️](https://gitlab.com/news-flash/news_flash_gtk)            | ✔️✔️                   | GReader          | ➖            | ⭐⭐      | ➖                           | ✔️                | ✔️       | ✔️    | ➖      | ➖          |
 | [Newsboat](https://newsboat.org/)                                       | GNU/Linux, macOS, FreeBSD | [✔️](https://github.com/newsboat/newsboat/)                   | ✔️✔️                   | GReader          | ➖            | ⭐        | ➖                             | ✔️                  | ✔️         | ➖     | ✔️       | ➖           |
+| [FluentFlame Reader](https://github.com/FluentFlame/fluentflame-reader)      | Windows, Linux, macOS| [✔️](https://github.com/FluentFlame/fluentflame-reader)       | Work in progress       | GReader          | ✔️            | ❔        | ❔                             | ❔                  | ✔️         | ➖     | ➖       | ➖           |
 
 | App                                                                                   | Platform    | Free Software                                                 | Maintained & Developed | API              | Works offline | Fast sync | Fetch more in individual views | Fetch read articles | Favourites | Labels | Podcasts | Manage feeds |
 |:--------------------------------------------------------------------------------------|:-----------:|:-------------------------------------------------------------:|:----------------------:|:----------------:|:-------------:|:---------:|:------------------------------:|:-------------------:|:----------:|:------:|:--------:|:------------:|