[JIRA] plugin store credentials in base64

When registering a JIRA instance in a project, the information and credentials are stored in plain base64 in the database, which mean that anybody able to connect to the database or read the dumps can log into the JIRA instance with the account of the linked user (which can be catastrophic depending the user's permissions). I would suggest encoding these data in openssl aes256-cbc or any securized way to store sensitive data. We want to define a set of [lightweight metrics](<https://docs.sentry.io/product/explore/metrics/>) that SDKs can automatically collect for e.g. framework, language or platform, focusing only on signals that **do NOT overlap with Tracing**. Ideally these metrics should give a quick sense of app or runtime health, … while deeper investigation will still rely on traces or profiles.<br><br>Examples**:** * Node.js runtime metrics (e.g., event loop delay, heap usage) * Prisma-related metrics in Next.js * Mobile CPU / memory usage to help surface potential ANRs or app hangs --- **Candidate Metrics (add more below)** * … *(please also add ideas, questions or examples in comments)*