upgrade: update flutter to 3.44.4, ignore rive in renovate (#770)

## Changes

- **Flutter 3.44.4**: Updates `.tool-versions` from `3.41.1-stable` to
`3.44.4-stable` (supersedes #762 which was at 3.44.2)
- **Ignore rive**: Adds `rive` to `ignoreDeps` in `renovate.json`
(closes #746)

Closes #762
Closes #746

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: AlexV525

.tool-versions

@@ -1 +1 @@
-flutter 3.41.1-stable
+flutter 3.44.4-stable

renovate.json

@@ -12,6 +12,7 @@
   "branchPrefix": "upgrade-renovate-",
   "dependencyDashboard": false,
   "ignorePaths": [".github/", "examples/**"],
+  "ignoreDeps": ["rive"],
   "major": {
     "minimumReleaseAge": "30 days"
   },