🛡️ Sentinel: [CRITICAL] Fix SQL injection risk in dynamic kwargs

[davidjuarezdev]

🚨 Severity: CRITICAL
💡 Vulnerability: The contains and remove database methods accept **kwargs that unpack directly into SQL condition strings. The validation of these columns was previously done with an assert. If a user runs streamrip using the python optimize flag (-O), assertions are stripped, allowing arbitrary column names to be unpacked into dynamic SQL queries, completely bypassing the validation.
🎯 Impact: Exploitation could allow an attacker to inject arbitrary SQL statements into the database query engine.
🔧 Fix: Removed assert validation and replaced it with an explicit ValueError that cannot be ignored by the interpreter. Also added the missing dictionary key validation to the remove method.
✅ Verification: Ran the test suite via poetry run pytest tests to ensure no legitimate internal database query mechanisms break from the stricter validation checking.

Includes a journal entry to .jules/sentinel.md documenting the learnings of this vulnerability constraint.

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PR created automatically by Jules for task 1275855855781349914 started by @davidjuarezdev