Fix punt and kickoff return yard narration

[tpitzel]

What changed

• Use play.ResultYards directly when narrating kickoff returns.
• Use play.ResultYards directly when narrating punt returns.
• Apply the same direct-return contract to both normal result output and stream output.
• Remove the obsolete field-position formulas that attempted to reconstruct return distance.

Why

The engine and stored play-by-play data already use ResultYards as the actual return distance. The API was interpreting that value a second time:

• Kickoff results displayed 100 - ResultYards.
• Punt results displayed line of scrimmage plus kick distance minus ResultYards.
• Stream output performed similar coordinate conversions.

That caused the human-readable result to disagree with the exported numeric Yards Gained and the ensuing field position. In game 9937, all 13 narrated punt/kickoff returns matched the obsolete formulas instead of the direct return value.

Impact

Play-by-play pages and CSV exports will display the same punt and kickoff return distance already stored in ResultYards. Because export narration is generated on request, historical games using the direct-return contract will also display correctly after this API version is deployed.

This is intentionally a one-file API formatter fix. It does not change the engine, database schema, Interface, or unrelated play-by-play fields.

Checks

• Based directly on current upstream master commit 844d1c7.
• go test ./...
• git diff --check upstream/master...HEAD
• One commit changing only managers/StatsManager.go.
• GitHub Actions completed the Go build successfully. The subsequent Azure registry login failed because deployment secrets are blank for the fork pull-request run, not because of a source or build failure.