v1.1.1

• Fix toMillis() violating its exact-ceil contract above 2^53 microseconds (~285 years): float division lost integer precision and the result was off by ±1 ms in both directions (including round-DOWN, the exact failure the contract forbids). Now pure integer arithmetic (intdiv + remainder), exact over the full range.
• Fix millis() — the one factory without an overflow guard: past PHP_INT_MAX the product silently became a float and the constructor threw an unrelated TypeError instead of the contractual InvalidArgumentException('Duration overflow: ...').
• Fix integer inputs to seconds()/minutes()/hours()/days() losing precision through the float path once the product exceeded 2^53 (e.g. seconds(9_223_372_036_853) came out 192 µs off): integer inputs now stay in integer arithmetic end to end, with the same overflow contract as plus().
• Sidestep the PHP >= 8.4 round() regression that returns n+1 for even integer-valued floats in [2^52, 2^53) (corrupted e.g. days(86165) by +1 µs on 8.4/8.5): round() is now skipped for float products at magnitude >= 2^52, where every representable double is already integral and rounding is a mathematical no-op.
• Docs: rewrite the __toString() docblock — the unit is chosen by boundary fall-through of rounded values, not by a "displayed value >= 1" rule (fall-through can legitimately print "0.999999min"); note the deliberate half-to-even vs half-away tie asymmetry between %g and the plain-integer day rendering. Both sub-unit fall-through outputs and the half-away rounding of the float factories are now pinned by tests.
• Test hardening: toMillis property against an integer-ceil oracle over the full [0, PHP_INT_MAX] range; microsRoundTrip/millisRoundTrip generators widened to the full valid ranges (the old caps were orders of magnitude below the bug zones); exactness properties and examples for the integer factories.

v1.1.0

• Check the README examples on every build with rasuvaeff/doc-exec: the usage
  block in README.md and README.ru.md is executed against the real
  Duration API, and composer build fails if an example stops matching it.
• Migrate the property-based test suite from the frozen rasuvaeff/property-testing 2.x to the new rasuvaeff/property-testing-testo adapter (drop-in, no PHP code changes; same #[Property] attribute and Gen API).
• Persist the property regression corpus across coverage CI runs (restore before tests, env PROPERTY_DB, save on completion of any non-cancelled run, including failed ones).
• Adopt rasuvaeff/rector-named-literals and apply the named-argument rule to literal calls.
• Raise rasuvaeff/property-testing-testo to ^0.6.
• Fix __toString(): a value that rounds up into the next unit (e.g. 999.5ms, which toMillis() rounds up to 1000) now falls through to that next unit ("0.9995s") instead of printing a misleading whole-number value in the wrong unit ("1000ms"). The same class of boundary artifact is now also closed at the s/min and min/h boundaries.
• Fix __toString(): day counts of 1,000,000 or more no longer render in scientific notation ("1.0e+6d"); they render as a plain integer ("1000000d").
• Fix plus(): overflowing PHP_INT_MAX microseconds now throws InvalidArgumentException('Duration overflow: ...') instead of silently promoting to float and letting the constructor throw an unrelated TypeError.
• Fix seconds()/minutes()/hours()/days(): overflowing PHP_INT_MAX microseconds now throws InvalidArgumentException('Duration overflow: ...') instead of silently producing a wrong (possibly zero) duration via an out-of-range float-to-int cast.

v1.0.0

• Initial release: type-safe, immutable, non-negative duration value object (Stringable).
• Stored internally as microseconds; factories zero/micros/millis/seconds/minutes/hours/days.
• Conversions: toMicros (exact), toMillis (rounded up via ceil), toSeconds (float), toMinutes (float).
• Saturating arithmetic plus/minus; static binary min/max.
• Comparisons compareTo/equals/isGreaterThan/isLessThan/isZero/isPositive.
• __toString() with fixed human-readable format (µs/ms/s/min/h/d, largest fitting unit).
• Property-based tests for algebraic laws (commutativity, associativity, antisymmetry, round-trip, absorption).