DOC-6652 document CDC latency workaround for SQL Server on Azure

[andy-stark-redis]

Note

Low Risk
Documentation-only change that describes an optional, customer-run sys.sp_cdc_scan polling workaround; no product code or runtime behavior is modified.

Overview
Adds a new Azure SQL Database CDC latency workaround section to the SQL Server RDI preparation guide, explaining how to reduce the fixed ~20s CDC capture cadence by running a single external worker that periodically executes sys.sp_cdc_scan.

Documents required privileges and single-replica constraints, a recommended scan loop/error handling strategy, interval tradeoffs and resource-impact warnings, plus example Kubernetes deployment YAML and SQL queries to verify scan frequency and staleness.

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[github-actions]

DOC-6652

[github-actions]

Staging links:
https://redis.io/docs/staging/DOC-6652-rdi-azure-workaroung/integrate/redis-data-integration/data-pipelines/prepare-dbs/sql-server/

[jit-ci]

🛡️ Jit Security Scan Results

✅ No security findings were detected in this PR

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[andy-stark-redis]

Thanks @cmilesb !