docs: update the docs and create a new announcement blog (#217)

## PR Checklist

Please check if your PR fulfills the following requirements:

- [x] The commit message follows our guidelines: CONTRIBUTING.md#commit
- [ ] Tests for the changes have been added (for bug fixes / features)
- [x] Docs have been added / updated (for bug fixes / features)

## PR Type

What kind of change does this PR introduce?

<!-- Please check the one that applies to this PR using "x". -->

```
[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[x] Documentation content changes
[ ] Other... Please describe:
```

## What is the new behavior?

- Update the docs to reflect the new changes
- Write an announcement blog post

Author: NachoVazquez

packages/docs/lumberjack-docs-app/blog/announcing-lumberjack-v19.md

@@ -0,0 +1,31 @@
+---
+title: 'Announcing Lumberjack v19: Angular 19 and no more Enum-based levels'
+description: Lumberjack v19 is here and it brings compatibility with Angular 19 and removes the old and depricated Enum-based levels.
+slug: announcing-lumberjack-v18
+authors:
+  - name: Nacho Vazquez
+    title: NgWorker and core maintainer of Lumberjack
+    url: https://github.com/NachoVazquez
+    image_url: https://github.com/NachoVazquez.png
+tags: [announcement, lumberjack, v19]
+image: https://pub-2294738bc2c249ff8040505bf960c018.r2.dev/logo.svg
+hide_table_of_contents: false
+---
+
+It took us a couple of months, but here we are. Lumberjack v19 is out, which brings compatibility with Angular 19 and removes the old and depricated Enum-based levels.
+
+## Angular 19
+
+With the new version of Angular out, we are happy to announce that Lumberjack is compatible with Angular 19.
+
+This closes issue: [#213](https://github.com/ngworker/lumberjack/issues/213)
+
+## Enum-based levels removal
+
+In version 17, we deprecated the usage of Enum-based levels in favor of string literal unions and announced they would be removed in version 19. See [here](https://ngworker.github.io/lumberjack/blog/announcing-lumberjack-v17). Mission accomplished.
+
+This change simplifies the API and reduces the library bundle size.
+
+## Wrapping Up
+
+There is nothing else to add; update your dependencies and enjoy the new version of Lumberjack.

packages/docs/lumberjack-docs-app/docs/compatibility.md

@@ -7,6 +7,7 @@ Refer to the following table to determine which version of Lumberjack is compati
 
 | Angular version | Lumberjack version |
 | --------------- | ------------------ |
+| 19.x            | 19.x               |
 | 18.x            | 18.x               |
 | 17.x            | 17.x               |
 | 16.x            | 16.x               |

packages/docs/lumberjack-docs-app/docs/log-drivers/log-drivers.md

@@ -51,7 +51,7 @@ levels for the HTTP driver as seen in the following example.
 ```ts
 import { bootstrapApplication } from '@angular/platform-browser';
 
-import { Level as LumberjackLevel, provideLumberjack } from '@ngworker/lumberjack';
+import { LumberjackLevel, provideLumberjack } from '@ngworker/lumberjack';
 import { provideLumberjackConsoleDriver } from '@ngworker/lumberjack/console-driver';
 import { provideLumberjackHttpDriver, withHttpConfig } from '@ngworker/lumberjack/http-driver';