fix(redisdistributed): scope Redis alert rules to release namespace

[PiyushSingh-ZS]

Description

charts/redisdistributed/templates/alerts.yaml rendered a per-release PrometheusRule, but 6 of 7 alert expressions had no namespace selector — they evaluated redis_* metrics across every namespace in the cluster while stamping this release's namespace/service as static labels. An alert about another namespace's Redis was mislabeled as this release.

Two were outright broken in multi-tenant clusters:

• RedisTooManyMasters — count(redis_instance_info{role="master"}) > 1 counts every master in every namespace; with ≥2 scraped Redis instances it was permanently true (constant false positive).
• RedisMissingMaster — only dropped to 0 if every Redis master cluster-wide disappeared, so it never fired when a single release's master was actually gone (silent failure of a critical alert).

Fix

Added namespace="{{ .Release.Namespace }}" to every metric selector, matching what RedisDown already does:

Alert	Metric now scoped
RedisMissingMaster	redis_instance_info
RedisTooManyMasters	redis_instance_info
RedisDisconnectedSlaves	redis_connected_slaves (both count/sum)
RedisReplicationBroken	redis_connected_slaves
RedisClusterFlapping	redis_connected_slaves
RedisRejectedConnections	redis_rejected_connections_total

RedisDown was already correctly scoped and is unchanged.

Chart bumped 0.0.9 → v0.0.10, repackaged into docs/, and index.yaml regenerated.

Type of Change

• Bug fix
• New feature
• Documentation update
• Chart configuration update

Checklist

• I have performed a self-review of my code
• helm lint passes without errors
• helm template renders valid YAML with all exprs namespace-scoped
• My changes generate no new warnings
• Chart repackaged and repo index updated

Fixes #297