feat: implement pinned messages

- render pinned events on the chat top
- support scroll up for several pinned messages
- ask to unpin messages
- add button to pin message
- fix some null-safety issues
- fix the Linux database directly for debug builds

Signed-off-by: TheOneWithTheBraid <the-one@with-the-braid.cf>

pubspec.lock

@@ -755,7 +755,7 @@ packages:
       name: js
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.6.3"
+    version: "0.6.4"
   latlong2:
     dependency: transitive
     description:
@@ -818,13 +818,15 @@ packages:
       name: material_color_utilities
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.1.3"
+    version: "0.1.4"
   matrix:
     dependency: "direct main"
     description:
-      name: matrix
-      url: "https://pub.dartlang.org"
-    source: hosted
+      path: "."
+      ref: main
+      resolved-ref: "788f8ea2a1fc6c3e417e74750c7200504275700f"
+      url: "https://gitlab.com/famedly/company/frontend/famedlysdk.git"
+    source: git
     version: "0.8.7"
   matrix_api_lite:
     dependency: transitive
@@ -965,7 +967,7 @@ packages:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.1"
   path_drawing:
     dependency: transitive
     description:
@@ -1355,7 +1357,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.1"
+    version: "1.8.2"
   sqflite:
     dependency: transitive
     description:
@@ -1418,21 +1420,21 @@ packages:
       name: test
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.19.5"
+    version: "1.20.1"
   test_api:
     dependency: transitive
     description:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.4.8"
+    version: "0.4.9"
   test_core:
     dependency: transitive
     description:
       name: test_core
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.4.9"
+    version: "0.4.11"
   timezone:
     dependency: transitive
     description:
@@ -1572,7 +1574,7 @@ packages:
       name: url_launcher_web
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.8"
+    version: "2.0.6"
   url_launcher_windows:
     dependency: transitive
     description:
@@ -1600,7 +1602,7 @@ packages:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.1"
+    version: "2.1.2"
   video_compress:
     dependency: "direct main"
     description:
@@ -1756,5 +1758,5 @@ packages:
     source: hosted
     version: "3.1.0"
 sdks:
-  dart: ">=2.15.1 <3.0.0"
-  flutter: ">=2.10.0"
+  dart: ">=2.16.0-100.0.dev <3.0.0"
+  flutter: ">=2.8.0"