chore: align config between YAML files and docs; add missing service sections

[hampsterx]

Summary

• Fix rds.proxy-base-port drift in test YAML (7000 → 7001 to match main YAML)
• Add missing apigatewayv2 section to main YAML, test YAML, and docs
• Add missing acm, opensearch proxy ports, appconfigdata value, and acm storage flush to test YAML
• Add appconfig, appconfigdata, and full ecr config to docs reference
• Clarify note about unlisted keys in docs

Review

Pre-reviewed by Codex and Gemini. Findings:

• Codex: improved docs note wording (applied)
• Gemini: trailing newline fix (applied), flagged pre-existing RDS code default drift (out of scope, Java source)
• Both confirmed apigatewayv2/acm/opensearch/appconfig/ecr additions are consistent across files

Changes

 docs/configuration/application-yml.md | +22 -1
 src/main/resources/application.yml    | +2  -0
 src/test/resources/application.yml    | +15 -2

Intentional test YAML differences (not drift)

• ecs.mock: true (test) vs false (main): CI doesn't need Docker for ECS tasks
• ECR minimal config in test: unit tests don't spin up a Docker registry
• storage.wal.compaction-interval-ms: 60000 (test) vs 30000 (main): slower compaction during tests

Test plan

• mvn test -B passes (1885/1886, 1 pre-existing ElastiCache failure unrelated to config)
• Verified service ordering matches across all three files
• Verified storage flush service ordering matches main YAML
• Diff reviewed for accuracy against main YAML as source of truth

[hectorvent]

Thanks @hampsterx