D1060213: Retry and Dead-letter handling to clean up the expended task tables

[raghavendran-gopalakrishnan]

https://internal.almoctane.com/ui/entity-navigation?p=131002/6001&entityType=work_item&id=1060213

Currently, in drop_deleted_task_tables if any error happens while dropping the task_* tables, the full procedure fails and exits, while keeping the problematic table(s) as a residue in the table, possibly causing issues in the subsequent runs.

• Added retry_count, last_error, and last_attempted_at columns to delete_log to track per-entry drop attempt history.
• Created the delete_log_failed dead-letter table for entries that exhaust all retries.
• drop_deleted_task_tables procedure now wraps each DROP TABLE in BEGIN...EXCEPTION WHEN OTHERS — failures increment retry_count and capture last_error.
• Move the retry-exhausted entries to dead-letter table delete_log_failed and so to keep the delete_log clean.

[buildmachine-sou-jenkins2]

CI Build Link:
https://sou-jenkins2.swinfra.net/job/JobService/job/JobService~job-service~1060213~CI

[buildmachine-sou-jenkins2]

The Documentation QA site for this branch has been built:
https://jobservice-ci-job-service-1060213-558227.glpages.otxlab.net