fix(mariadb): make cluster chart mode select replication/galera topology

[weicao]

Summary

The addons-cluster/mariadb chart cannot select the replication or galera topology. mode only changes the replica count; the Cluster always resolves an ambiguous componentDef.

Root cause

templates/cluster.yaml used:

componentSpecs:
  - name: mariadb
    componentDef: mariadb
    replicas: {{ include "mariadb-cluster.replicas" . }}

componentDef: mariadb is a name prefix, and the addon ships three CmpDs:

• mariadb-<version> (standalone)
• mariadb-replication-merged-<version> (replication)
• mariadb-galera-<version> (galera)

The prefix mariadb matches all three, so it cannot deterministically select replication or galera. Meanwhile the only topology lever is mode, which templates/_helpers.tpl uses solely to compute replicas (standalone → 1, else .Values.replicas). It never selects a component definition.

values.schema.json further locked this down: mode enum was ["standalone"] only, and replicas had maximum: 1. So even the schema forbade anything but a single standalone node.

The addon already ships a ClusterDefinition named mariadb with three named topologies (standalone default, replication, galera), each pinning the correct compDef by full name — but the cluster chart did not use it.

Fix

Use the KB-native topology selector (same idiom as clickhouse / apecloud-mysql cluster charts):

spec:
  clusterDef: mariadb
  topology: {{ .Values.mode }}
  componentSpecs:
    - name: mariadb
      replicas: {{ include "mariadb-cluster.replicas" . }}

• mode maps 1:1 to the ClusterDefinition topology names (standalone / replication / galera), so topology: {{ .Values.mode }} resolves the correct compDef.
• values.schema.json: mode enum expanded to ["standalone", "replication", "galera"]; replicas maximum raised from 1 to 5 (standalone is still forced to 1 by the helper).
• values.yaml: documented the mode options and replica guidance (replication ≥ 2, galera odd ≥ 3).

Verification

helm template for all three modes renders clusterDef: mariadb + the correct topology:, with no ambiguous componentDef field; standalone forces replicas: 1, replication/galera honor the set value.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (35e0ded) to head (6d33a12).

Additional details and impacted files

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  Coverage   0.00%   0.00%           
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  Files        144     144           
  Lines      23013   23013           
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  Misses     23013   23013           

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