feat(sandbox): type and verify default templates

[miclle]

Summary

• type SandboxClient.listDefaultTemplates() as Promise<TemplateInfo[]>
• add focused success, API error, TypeScript, and live integration coverage
• show default-template details in the template example and keep mutation opt-in
• add reproducible unit and .env-backed integration commands

Why

The runtime GET /default-templates wrapper already existed, but its public TypeScript contract still returned any and the behavior lacked focused error-path and live read-only validation. This aligns the Node.js SDK surface and verification with qiniu/go-sdk#230.

Validation

• npm run test:sandbox:default-templates — 2 passing
• npm run test:sandbox:integration:default-templates — 1 passing, 8 live templates from the root .env
• QINIU_SANDBOX_TEMPLATE_MUTATION_EXAMPLE=false node examples/sandbox_templates.js — live read-only example passed
• npm run test:sandbox — 124 passing
• npm run check-type
• targeted ESLint and node --check examples/sandbox_templates.js
• git diff --check
• npm pack --dry-run --json

[fennoai]

I found two actionable gaps in the new default-template typing coverage; details are inline.

[fennoai]

Review Complete

• No actionable findings.
• npm run test:sandbox:default-templates — 2 passing.
• npm run check-type — passed.
• Targeted ESLint, node --check, and git diff --check — passed.
• npm run test:sandbox — 124 passing.
• npm pack --dry-run --json — passed.

View job run

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.41%. Comparing base (32685e9) to head (abf9f73).
⚠️ Report is 6 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #456      +/-   ##
==========================================
- Coverage   93.41%   93.41%   -0.01%     
==========================================
  Files          14       14              
  Lines        2006     2050      +44     
==========================================
+ Hits         1874     1915      +41     
- Misses        132      135       +3     

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[fennoai]

No actionable findings. The default-template typing, read-only example behavior, error-path coverage, and integration-test gating are consistent with the existing sandbox client. Focused and full sandbox validation passed.