bug: /api/tasks may not finalize prepared statement on validation errors

[gowthamrdyy]

Problem\nPOST /api/tasks prepares an SQLite statement, but in some validation-error paths it returns a response without finalizing the prepared statement. This can leak resources and may lead to "database is locked" issues under load or repeated requests.\n\n# Current Behavior\nWhen all provided tasks are invalid and inserted = 0, the handler can respond before stmt.finalize() is called.\n\n# Expected Behavior\nAlways call stmt.finalize() before responding (success or error), regardless of which path is taken.\n\n# Steps to Reproduce\n1. Start the server\n2. POST to /api/tasks with an invalid payload (missing title/subject/due_at)\n3. Repeat a few times; prepared statements should not accumulate

[gowthamrdyy]

Hi maintainers — I’d like to work on this for GSSoC 2026. Please assign this issue to @gowthamrdyy.