Fix #1015: round award totals after summing

[gemshrine]

Fixes #1015.

Award::Bill#points now sums raw line values and rounds the final total once, so fractional lines are not independently rounded and inflated. Added coverage for two half-point lines.

[yegor256]

The fix itself looks right and CI is green, but I am holding off on merging for two reasons.

First, #793 ("#779: round the total once, not every line of the bill") is already open for the same defect and assigned for review, so one of the two should be closed before either lands.

Second, greeting still prints each line through whole(l[:v]), so after this change the printed line values can add up to something other than the printed total: two lines of 0.5 render as "+1 ...; +1 ..." with a total of "+1". That may well be the intended trade-off, but since this decides what contributors are actually paid, it deserves a deliberate call rather than a drive-by merge.

Assigning to @yegor256.

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Generated by Claude Code

[yegor256]

Thanks for the fix, merged.

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Generated by Claude Code

[0crat]

@gemshrine Thanks for the contribution! You've earned +20 points: +24 as the base award, minus 4 points for contributing fewer than 30 hits-of-code (9 in this case), as per policy. Please keep them coming. Your running score is +6206; don't forget to check your Zerocracy account too.