fix(cli): read module-path from config when no generate entries exist

[omerarslan0]

When spacetime.json has module-path at the root level but no generate block, spacetime generate ignores it and defaults to spacetimedb/.

The fallback path in exec_ex() created a CommandConfig with an empty HashMap, discarding entity-level fields from the config. Fix by passing the root config's additional_fields instead.

Closes #4475

Description of Changes

When spacetime.json contains module-path at the root level but no generate block, spacetime generate ignores the configured path and defaults to spacetimedb/. The root cause is in exec_ex(): when get_filtered_generate_configs() returns empty (no generate entries), the fallback CommandConfig was created from an empty HashMap, discarding module-path from the root entity's additional_fields. Fixed by passing loaded.config.additional_fields.clone() instead of HashMap::new().

API and ABI breaking changes

None. This is a bug fix that makes the existing module-path config option work as documented.

Expected complexity level and risk

1 - Trivial. Single line change from HashMap::new() to loaded.config.additional_fields.clone() in the fallback path. The existing code paths for configs with generate entries are unaffected.

Testing

Added regression test test_root_module_path_without_generate_entries_is_forwarded that validates module-path from root config without generate entries is properly forwarded. Existing tests remain unmodified and should continue to pass.

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2 out of 3 committers have signed the CLA.

✅ omerarslan0
✅ cloutiertyler
❌ sehawq

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[bfops]

Thank you for opening a PR for this! Unfortunately I'm getting a different error in this case now.

[omerarslan0]

@bfops Can you check again?

[omerarslan0]

Is there any progress? @bfops

[bfops]

Is there any progress? @bfops

Thank you for updating it. I will try to do another review soon!

[omerarslan0]

Is there any progress? @bfops

[bfops]

@sehawq I will try to get another review on this soon!