Align temporal string schema evolution with Java

[JingsongLi]

What changes

Align the Native reader's existing temporal-to-character schema evolution with Java:

• Format TIME with DateTimeUtils' precision loop, including .0 for whole seconds and negative-millisecond normalization.
• Format TIMESTAMP with a space separator and its declared minimum fraction width, retaining significant nanoseconds.
• Format TIMESTAMP_LTZ in the process local time zone without an ISO zone suffix.
• Apply Java CHAR padding and VARCHAR truncation to scalar temporal casts.
• Reuse the scalar conversion inside ARRAY/MAP/ROW string rendering, preserving NULL containers and nested NULLs.
• Share temporal formatting with non-legacy partition paths and fix TIME's whole-second partition text.
• Preserve Java's signed epoch-day narrowing, four-digit year rendering, and millisecond wrapping for ordinary timestamps outside datetime ranges.

The behavior lives in Rust core; the Python bindings need no new API or conversion logic. Legacy partition formatting is unchanged. No dependencies are added.

Evidence

An existing-capability probe exercised 85 Python-supported atomic schema changes through REST tables. It identified TIME/TIMESTAMP/LTZ string differences. Re-running the same probe after these changes found no mismatches.

Java references: TimestampToStringCastRule, TimeToStringCastRule, DateTimeUtils, BinaryStringUtils, and Timestamp.toLocalDateTime. Actual Java CastExecutors were also exercised for precision, bounded strings, time zones, pre-epoch timestamps and wide years.

Verification

• 73 focused Rust tests: evolution_string, nested_evolution and partition_utils.
• cargo +1.98.0 fmt --all -- --check.
• cargo +1.98.0 clippy --locked --all-targets --workspace --features fulltext,vortex -- -D warnings.
• Rebuilt Python extension and ran 195 REST schema-evolution tests with Native planning/reading/writing/committing enabled: 447 Native reads, 261 writes and commits.
• LTZ REST cases also passed in America/New_York and Asia/Shanghai, including winter/summer instants.

Companion Python PR: apache/paimon#10519, with Java-aligned pure-Python casts and cross-path regressions. Its Native CI will require this Rust change to be merged first.

[leaves12138]

Reviewed the implementation and focused tests. I found no blocking issues.