🪲 BUG-#221: Fix StorageFile crash on corrupted task files

[FernandoCelmer]

Description

Fix StorageFile.post() and StorageFile.get() crashing with AttributeError when task files contain non-JSON content (corrupted, interrupted writes, manual edits).

Issue: 📌 ISSUE-#221

Changes

• Validate read_file return type in both post() and get() — only use result if it's a list
• Corrupted files are silently treated as empty (overwritten on next write)

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes