chore: clean unused code and centralize core constants

[xiaomu120413]

Summary

• remove unused ArkTS tests, duplicate test wrappers, and dead E2E helper APIs
• remove tracked local E2E credentials and ignore machine-local configuration
• align README, PRD, RFC, AGENTS, E2E docs, and permission module design with the current implementation
• centralize core dashboard ID types, peripheral reason codes, and log display strings

Validation

• hvigorw test --no-daemon --mode module -p product=default -p module=entry@default
• hvigorw assembleHap --no-daemon --mode module -p product=default -p module=entry@default
• python scripts/check_docs_consistency.py
• python scripts/e2e/tools/validate_test_assets.py
• git diff --check

Design documentation

• updated docs/03-模块设计/权限管理组件设计说明.md to match the implemented account/application policy capabilities
• the final constant cleanup is behavior-preserving and does not require additional module design changes

Scope

• ukey/ is intentionally untouched