fix(sla): freeze resolution overdue timer while ticket is paused

[RitvikSardana]

A ticket paused after its resolution deadline showed an "Overdue by" number that kept climbing while the SLA clock was stopped, with nothing on the card or popover saying the ticket was on hold.

• Freeze the overdue duration at on_hold_since when the ticket is paused, so it reports the breach that happened before the pause instead of counting hold time as lateness.
• Show the "On hold since" row for overdue metrics, not just hold.

The card keeps reading "Overdue" rather than "On Hold" here: the SLA already failed before the pause (agreement_status: "Failed"), and a blue "On Hold" would hide that.

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[greptile-apps]

Confidence Score: 4/5

The PR appears safe to merge, with regression coverage for the paused-overdue display recommended.

The changed duration and popover paths are coherent, but their time-dependent behavior is currently untested.

Files Needing Attention: desk/src/composables/useSLA.ts; desk/src/components/ticket-agent/TicketSLA.vue

Prompt To Fix All With AI

### Issue 1
desk/src/composables/useSLA.ts:178-182
**Cover the paused-overdue regression**

Add a regression test for a resolution SLA breached before pausing, covering both the frozen overdue duration and the associated hold timestamp; without it, future changes can silently restore the growing timer or drop its context.

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

_{Reviews (1): Last reviewed commit: "fix(sla): freeze resolution overdue time..." | Re-trigger Greptile}

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.76%. Comparing base (c3ae467) to head (a98f1bf).
⚠️ Report is 3 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #3709   +/-   ##
========================================
  Coverage    73.76%   73.76%           
========================================
  Files          148      148           
  Lines        10841    10841           
========================================
  Hits          7997     7997           
  Misses        2844     2844           

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