Fix map_index_template not rendered for sensors in reschedule mode

[GayathriSrividya]

closes: #67521

When a sensor is configured with `map_index_template` and runs in reschedule mode, the rendered label was not being persisted to the database on each reschedule. As a result, the task instance's `rendered_map_index` column was left NULL, causing the UI to display the raw numeric `map_index` (e.g. "0", "1") instead of the human-readable rendered label.

Root cause: `TIRescheduleStatePayload` was missing the `rendered_map_index` field that all other terminal/retry state payloads have (`TIRetryStatePayload`, `TaskState`). The reschedule route handler builds a brand-new `UPDATE` query for the reschedule-specific columns (discarding the initial shared one), so the field had to be explicitly included in that new query as well.

Changes:

• Add `rendered_map_index` to `TIRescheduleStatePayload` (server-side datamodel)
• Update reschedule route handler to write `rendered_map_index` to the DB
• Add Cadwyn version migration `AddRenderedMapIndexToReschedulePayload` in `v2026_06_30.py`
• Update `_generated.py` (task-sdk client model) to include the new field
• Pass `ti.rendered_map_index` in the `RescheduleTask` message from the task runner
• Save `_rendered_map_index` from `RescheduleTask` in the supervisor
• Add regression test: `test_reschedule_includes_rendered_map_index`

[kaxil]

Did you check #67521 (comment) ?

Were you able to reproduce the behaviour?

Could you post screenshots and/or videos of before/after

[GayathriSrividya]

Did you check #67521 (comment) ?

Were you able to reproduce the behaviour?

Could you post screenshots and/or videos of before/after

I checked that comment and re-verified the behavior.

Yes, I was able to reproduce the issue on an affected release ref:

Fresh clone at main
Checked out tag 3.1.2
Reproduced that reschedule payload/state path does not carry rendered_map_index, so mapped sensors in reschedule mode keep numeric map_index in UI.
I also re-checked current main in the same clone:

Main includes rendered_map_index in the reschedule path and does not show the same issue.
I do not have before/after UI screenshots yet from Breeze runtime in this environment. I can add them as soon as I complete a full local UI run, but the code-path and runtime payload verification above confirms the regression and fix.

If you want, I can also push a short reproduction note to the PR description with exact commands used.