fix(config): guard against None when meta lacks generated_by key

[devteamaegis]

What's broken

In load_settings(), the condition meta.get("generated_by") <= "0.3.0" raises TypeError when the [meta] section exists in config.toml but the generated_by key is absent. meta.get("generated_by") returns None, and None <= str is unsupported in Python 3. The guard not meta only short-circuits on None or empty dict, not on a non-empty dict with a missing key.

Why it happens

The version comparison was written assuming meta.get("generated_by") always returns a string, but the key can be missing even when [meta] is present.

Fix

Extract generated_by = meta.get("generated_by") if meta else None before the comparison. The existing if not generated_by branch handles both None (missing key) and empty string, so the behaviour is correct: a config without generated_by is treated as outdated.

Test

Added TestLoadSettingsMetaGuard.test_meta_section_without_generated_by_raises_value_error which writes a TOML file with [meta] but no generated_by, monkeypatches config_file, and asserts ValueError (not TypeError) is raised.

Fixes #2942

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Summary by cubic

Guard against missing generated_by in [meta] during config loading to prevent a TypeError; such configs are treated as outdated and raise a clear ValueError.

^{Written for commit f71dae9. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 2 files

_{Re-trigger cubic}

[dokterbob]

@codex review

[dokterbob]

LGTM, thanks!

[dokterbob]

Code looks good, thanks! Please fix formatting/linting issues!

@devteamaegis