refactor: rename environment variables and update related configurations

- Updated environment variable names from JERAPAH_FLOW_* to JFLOW_* for consistency and clarity.
- Adjusted database path handling in knexfile.js to reflect the new variable naming.
- Modified logging and retention days configurations to use the new variable names.
- Ensured that the JWT secret and secrets key checks are aligned with the new naming convention.
- Updated workflow test storage prefix to match the new project branding.

This refactor enhances the clarity of environment variable usage and aligns with the project's rebranding efforts.

packages/server/registry.js

@@ -323,7 +323,7 @@ export function createRegistry(server) {
       pruneTask.destroy();
       pruneTask = null;
     }
-    const days = Number(process.env.JERAPAH_FLOW_RETENTION_DAYS ?? process.env.SCRUNNER_RETENTION_DAYS ?? 30);
+    const days = Number(process.env.JFLOW_RETENTION_DAYS ?? 30);
     pruneTask = cron.schedule(
       "0 0 * * *",
       async () => {