fix: use Python-level default for Specification.complexity to prevent MissingGreenlet error

[octo-patch]

Fixes #1105

Problem

Specification.complexity was declared with server_default=Complexity.HARD. A server_default only provides a database-level DEFAULT clause; SQLAlchemy does not set the attribute value at the Python level when the object is first created. Before the object is committed and the row is fetched back from the database, accessing self.complexity returns None, which causes SQLAlchemy to attempt a lazy IO operation outside an async greenlet context, raising:

MissingGreenlet: greenlet_spawn has not been called; can't call await_only() here.

This crash happens in Specification.clone() on line 55 when the spec object has been created but not yet persisted (or when an existing DB row has a NULL complexity from an older migration).

Solution

• Change server_default=Complexity.HARD → default=Complexity.HARD so SQLAlchemy sets the value on the Python object at instantiation time, consistent with how all other string columns (description, architecture, etc.) are configured in this model.
• Add or Complexity.HARD fallback in clone() to safely handle any existing rows in the database that have a NULL complexity value.

No database migration is needed: the schema-level DEFAULT was already applied by the original server_default; this change only affects Python-side attribute initialization.

Testing

• Reproduced the error by instantiating a Specification without flushing, then calling clone()
• Confirmed that after the fix, complexity is immediately available as "hard" without a database round-trip

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❌ Zvonimir Sabljic
❌ MarkoBosnjak98
❌ LeonOstrez
❌ github-actions[bot]

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