[bug][mdatagen] Auto-enable v1 metrics when legacy is enabled

[osullivandonal]

Description

When the v1 feature gate is on and a legacy metric is enabled, programmatically enable the corresponding v1 metric so users don't need to update their config to get v1 metric emitted.

Link to tracking issue

Fixes #15650

Authorship

• I, a human, wrote this pull request description myself.

[codspeed-hq]

Merging this PR will improve performance by 22.45%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚡ 1 improved benchmark
✅ 2 untouched benchmarks
🗄️ 4 archived benchmarks run¹

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	BenchmarkTraceSizeSpanCount	60 ns	49 ns	+22.45%

Tip

Curious why this is faster? Comment @codspeedbot explain why this is faster on this PR, or directly use the CodSpeed MCP with your agent.

---

_{Comparing osullivandonal:mdatagen-fix-auto-enable-versioned-metrics (bcde0c1) with main (52e6bf4)}

Footnotes

1. 4 benchmarks were run, but are now archived. If they were deleted in another branch, consider rebasing to remove them from the report. Instead if they were added back, click here to restore them. ↩

[codecov]

Codecov Report

❌ Patch coverage is 0% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.02%. Comparing base (ee490df) to head (bcde0c1).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...tionscraper/internal/metadata/generated_metrics.go	0.00%	6 Missing and 2 partials ⚠️

❌ Your patch check has failed because the patch coverage (0.00%) is below the target coverage (95.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #15651      +/-   ##
==========================================
- Coverage   91.03%   91.02%   -0.02%     
==========================================
  Files         729      729              
  Lines       48491    48499       +8     
==========================================
  Hits        44144    44144              
- Misses       3020     3026       +6     
- Partials     1327     1329       +2     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.