feat: upgrade packages to fix compatibility errors

[mpast]

Fixes for #172

Summary

Recent APKs targeting Android 16/API 36 could leave scans frozen at 20% during decompilation. The existing APK toolchain was outdated, JADX execution was unbounded, and decompilation failures were not handled consistently.

This change updates the toolchain and makes the decompilation stage bounded, recoverable, and observable.

What changed

File	Change
Dockerfile	Upgrades JADX from 1.4.7 to 1.5.5, makes its launchers executable, and creates a writable home directory for the non-root worker user.
requirements.txt	Upgrades Androguard from 3.4.0a1 to 4.1.4 and updates drf-yasg for compatibility with the current Django REST Framework version.
app/analysis.py	Replaces blocking os.system() execution with controlled subprocess handling, timeout enforcement, process-group termination, partial-output cleanup, output validation, bounded diagnostics, and atomic completion markers.
app/worker/tasks.py	Converts Celery exceptions into JSON-safe responses for the scan-state endpoint.
app/tests.py	Adds regression coverage for successful, partial, failed, timed-out, and interrupted decompilation paths.