fix(summary): bound SummaryParser.buf on newline-less log floods (D3)

[saadqbal]

Closes#226. Deferred finding D3 from the v0.8.0 review (#220). Low severity.

The bug

SummaryParser.Feed accumulates bytes into p.buf until it sees a \n. The display path caps an oversized tqdm line via displayLineMax (16 MB) in streamDisplayAndParse and drains the rest — but the drained bytes still flow through the TeeReader into Feed. So a pathological ingestor emitting many MB of \r-redraws with no \n for the life of a (up to 1h JobWatchTimeout) run grows p.buf without the display-side cap ever applying to the parser.

The fix

Bound buf at parserLineMax, defined as = displayLineMax — same submit package, referenced directly so the two paths can't drift. When the partial newline-less line passes the ceiling, drop it and enter a drop-until-newline state (droppingLine) so the oversized line's tail is discarded too rather than parsed as a spurious fresh line. FlushLine honors the same state at EOF.

A real banner line is tens of bytes, so newline-less content past 16 MB can never be one — dropping is safe, and the parser still recovers to parse the closing banner once a \n finally lands. buf's persistent size is now bounded by parserLineMax (peak is parserLineMax + one Feed chunk, transient).

Test

TestSummaryParser_BufferBoundedOnNewlinelessFlood feeds a >2×parserLineMax newline-less flood in bounded chunks, asserts buf never exceeds parserLineMax, then feeds a terminating \n + a real banner and asserts it still parses.

go test ./internal/submit/, go vet, gofmt all clean.

🤖 Generated with Claude Code

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Note

Low Risk
Defensive bounds on log parsing only; legitimate banners are tiny and recovery after a terminating newline is covered by tests.

Overview
Caps SummaryParser memory when ingest logs never emit a newline — e.g. long tqdm \r redraws that the display path already drains but still pass through the TeeReader into Feed.

parserLineMax is set to displayLineMax (16 MB) so parser and display limits stay aligned. Once a partial line exceeds that, Feed resets the buffer and sets droppingLine until the next \n, so the rest of the junk line is skipped instead of being parsed as a new line. FlushLine applies the same rule at EOF so a truncated tail is not fed to feedLine.

Adds TestSummaryParser_BufferBoundedOnNewlinelessFlood: multi-chunk newline-less flood keeps buf ≤ parserLineMax, then \n + a real banner still parses correctly.

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