## Context
Improving the "blocked by" visualisation for database connections - to
accommodate the situation whereby there might be a chain of blocked
process. Intention is so that users can identify whats the root process
that's blocking everything - and from there decide if they want to
terminate the process or not.
Also brings `ActivityRow` out into its separate file since `Activity` is
getting big
<img width="473" height="299" alt="image"
src="https://github.com/user-attachments/assets/21d0d223-5dbd-49d5-877c-815c78cb7482"
/>
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## Summary by CodeRabbit
* **Refactor**
* Streamlined the database activity view by separating the single-row
rendering into its own component, keeping the same end-user experience
(status badge, query/“No query”, duration warnings, blocking details,
PID copy, and actions).
* Kept “Terminate” behind confirmation prompts and preserved role-based
restrictions for when termination is available.
* **Improvements**
* Standardized how activity durations are calculated and how status
badges are styled for consistent display.
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Joshen Lim
63e2eb3ca6