Fix .vorta-init.json import for Flatpak environments

[Nishani-B]

Fixes #2464

Description

Vorta looks for .vorta-init.json using Path.home(), which in a Flatpak
sandbox resolves to the sandboxed directory because Flatpak overrides the
HOME environment variable. Both Path.home() and os.path.expanduser("~")
read HOME, so the previous fallback was a no-op.

Solution

Use pwd.getpwuid(os.getuid()).pw_dir to query the password database directly,
bypassing any HOME override. This correctly resolves the real home directory
even inside a Flatpak sandbox.

Changes addressing review feedback

• Fix: replaced os.path.expanduser("~") with pwd.getpwuid(os.getuid()).pw_dir
  to actually bypass the Flatpak HOME override (previous fallback was a no-op)
• Fix: restored docstring to correct position in bootstrap_profile()
  (was placed after an executable line, making it a dead string expression)
• Fix: reverted unrelated indentation change in notifier.deliver()
• Fix: removed redundant .is_file() check after the for-loop
• Add: tests/unit/test_bootstrap_profile.py — 11 tests covering
  Flatpak HOME bypass, path resolution, default profile creation,
  file lifecycle, and docstring placement

Types of changes

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

Checklist

• I have read the CONTRIBUTING guide
• My code follows the code style of this project
• I have added tests to cover my changes
• All new and existing tests passed

[m3nu]

Thanks for working on this. The issue is real, but I don't think this PR correctly addresses it.

Core issue: os.path.expanduser("~") and Path.home() are identical

Path.home() is implemented by calling os.path.expanduser("~"). Both check the HOME env var first. In a Flatpak sandbox where HOME is overridden to the sandboxed directory, both return the same sandboxed path. The "fallback" added here is always a no-op.

To actually bypass a Flatpak HOME override, you'd need to query the password database directly:

import pwd
real_home = Path(pwd.getpwuid(os.getuid()).pw_dir)

Other issues

1. Broken docstring — The docstring was moved below the first executable line (bootstrap_file = bootstrap_file or ...), turning it from a method docstring into a dead string expression.

2. Unrelated indentation change — The closing paren of notifier.deliver() was re-indented without reason.

3. Redundant .is_file() check — After the for-loop already confirmed the file exists and set bootstrap_file, the original if bootstrap_file.is_file(): check runs again redundantly.

4. No tests for a path-resolution change that's difficult to verify manually across environments.

[Nishani-B]

I've addressed all the review feedback in the latest commit

Here's a summary of what was fixed:

• Replaced os.path.expanduser("~") with pwd.getpwuid(os.getuid()).pw_dir
  to correctly bypass the Flatpak HOME override

• Restored the docstring to the correct position in bootstrap_profile()

• Reverted the unrelated indentation change in notifier.deliver()

• Removed the redundant .is_file() check after the for-loop

• Added tests/unit/test_bootstrap_profile.py with 11 tests covering
  path resolution, Flatpak HOME bypass, file lifecycle, and docstring placement

  Please let me know if anything else should be adjusted.