…tograms

This commit implements counter reset hint comparison in the promqltest
framework to address issue prometheus#17615. Previously, while test definitions
could specify a counter_reset_hint in expected native histogram results,
the framework did not actually compare this hint between expected and
actual results.

The implementation adds optional comparison logic to the
compareNativeHistogram function:
- If the expected histogram has UnknownCounterReset (the default),
  the hint is not compared (meaning "don't care")
- If the expected histogram explicitly specifies CounterReset,
  NotCounterReset, or GaugeType, it is verified against the actual
  histogram's hint

This allows tests to verify that PromQL functions correctly set or
preserve counter reset hints while maintaining backward compatibility
with existing tests that don't specify explicit hints.

Fixes prometheus#17615

Signed-off-by: aviralgarg05 <gargaviral99@gmail.com>

The test at line 1283 for avg_over_time(nhcb_metric[13m]) incorrectly
expected counter_reset_hint:gauge in the result. However, the actual
avg_over_time implementation does not explicitly set the CounterResetHint
to GaugeType on its output histogram.

With the new counter reset hint comparison logic added to the promqltest
framework (which compares hints when explicitly specified in expected
results), this incorrect expectation was now being caught.

This fix removes the incorrect counter_reset_hint:gauge from the expected
result, allowing the test to correctly verify the avg_over_time behavior
without asserting a specific hint value that the function does not set.

The counter reset hint comparison logic works as designed: if the expected
histogram has UnknownCounterReset (the default when not specified), no
comparison is performed. Only when a hint is explicitly specified in the
test expectation will it be compared against the actual result.

Fixes the test failure introduced by the counter reset hint comparison
feature in promqltest.

Signed-off-by: Aviral Garg <aviralg2106@gmail.com>
Signed-off-by: aviralgarg05 <gargaviral99@gmail.com>

…ation

This commit addresses the PR feedback for issue prometheus#17615. The previous
implementation could not distinguish between:
- No counter reset hint specified (meaning "don't care")
- counter_reset_hint:unknown explicitly specified (meaning "verify it's unknown")

Changes:
- Added CounterResetHintSet field to parser.SequenceValue to track
  whether counter_reset_hint was explicitly specified in the test file
- Modified buildHistogramFromMap to set this flag when the hint is
  present in the descriptor map
- Updated newHistogramSequenceValue helper and histogramsSeries
  functions to propagate the flag through histogram series creation
- Updated yacc grammar to use the new helper function
- Modified compareNativeHistogram to accept the flag and only compare
  hints when explicitly specified

This allows tests to:
1. Not specify a hint (no comparison, backward compatible)
2. Explicitly specify counter_reset_hint:unknown (verify it's unknown)
3. Explicitly specify counter_reset_hint:gauge/reset/not_reset (verify match)

Fixes prometheus#17615

Signed-off-by: aviralgarg05 <gargaviral99@gmail.com>