Small improvements, part 2

[JavaSaBr]

Changes Summary

1. New Array API: tryTrimTo(int)

• Added UnsafeMutableArray.tryTrimTo(int internalStorageSize) method to safely resize internal storage
• Implemented in AbstractMutableArray with validation logic:
  • Returns unchanged if requested size exceeds current capacity
  • Returns unchanged if requested size is less than current element count
  • Performs trimming for valid requests
• Includes complete javadoc with @since 10.0.alpha14 tag

2. Collection Optimization Pattern

Applied early-exit isEmpty() checks across dictionary implementations to avoid unnecessary allocations and iterations:

• AbstractHashBasedIntToRefDictionary: 7 methods optimized (keys, values, iterator)
• AbstractHashBasedLongToRefDictionary: 7 methods optimized
• AbstractHashBasedRefToRefDictionary: 7 methods optimized

Methods optimized include:

• iterator() — returns empty iterator immediately
• keys() (all overloads) — returns empty arrays/containers
• values() (all overloads) — returns empty arrays/containers

3. Documentation

• Added comprehensive javadoc to tryTrimTo() method
• Updated .github/copilot-instructions.md with "Collections optimization pattern" section

Testing & Validation

• Module build: ./gradlew :rlib-collections:build ✅
• Full build verification: ./gradlew clean build (recommended before merge)

[Copilot]

Pull request overview

Bumps the version to 10.0.alpha14 and applies two collection-level improvements: a new tryTrimTo(int) API on UnsafeMutableArray for safe storage shrinking, and pervasive early-exit isEmpty() short-circuits across the three hash-based dictionary implementations to avoid unnecessary allocations and iterations. Also adds a new .github/skills/generate-branch-summary.md skill doc and a "Collections optimization pattern" section to the Copilot instructions.

Changes:

• Add UnsafeMutableArray.tryTrimTo(int) and implement it in AbstractMutableArray.
• Add isEmpty() fast paths to iterator(), keys(...) and values(...) overloads in the Int/Long/Ref hash dictionaries.
• Bump rootProject.version and README example version from 10.0.alpha13 → 10.0.alpha14; add Copilot/skill documentation.

Reviewed changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
rlib-collections/src/main/java/javasabr/rlib/collections/array/UnsafeMutableArray.java	Adds new tryTrimTo(int) interface method with javadoc.
rlib-collections/src/main/java/javasabr/rlib/collections/array/impl/AbstractMutableArray.java	Implements tryTrimTo with capacity/size validation.
rlib-collections/src/main/java/javasabr/rlib/collections/dictionary/impl/AbstractHashBasedIntToRefDictionary.java	Adds early-exit isEmpty() checks in iterator/keys/values overloads.
rlib-collections/src/main/java/javasabr/rlib/collections/dictionary/impl/AbstractHashBasedLongToRefDictionary.java	Same isEmpty short-circuits for the long-keyed variant.
rlib-collections/src/main/java/javasabr/rlib/collections/dictionary/impl/AbstractHashBasedRefToRefDictionary.java	Same isEmpty short-circuits for the ref-keyed variant.
build.gradle	Version bump to 10.0.alpha14.
README.md	Updates the example rlibVersion to 10.0.alpha14.
.github/copilot-instructions.md	Documents the new collections optimization pattern.
.github/skills/generate-branch-summary.md	New skill describing how to generate a branch summary.

[github-actions]

Overall Project	54.4% -0.2%	🍏
Files changed	66.67%	🍏

File	Coverage
AbstractHashBasedRefToRefDictionary.java	94.67% -2.17%	🍏
AbstractHashBasedLongToRefDictionary.java	89.39% -4.06%	🍏
AbstractHashBasedIntToRefDictionary.java	89.34% -4.08%	🍏
AbstractMutableArray.java	79.02% -5.59%	❌

[github-actions]

Overall Project	54.36% -0.2%	🍏
Files changed	66.67%	🍏

File	Coverage
AbstractHashBasedRefToRefDictionary.java	94.67% -2.17%	🍏
AbstractHashBasedLongToRefDictionary.java	89.39% -4.06%	🍏
AbstractHashBasedIntToRefDictionary.java	89.34% -4.08%	🍏
AbstractMutableArray.java	79.02% -5.59%	❌

[github-actions]

Overall Project	54.38% -0.2%	🍏
Files changed	66.67%	🍏

File	Coverage
AbstractHashBasedRefToRefDictionary.java	94.67% -2.17%	🍏
AbstractHashBasedLongToRefDictionary.java	89.39% -4.06%	🍏
AbstractHashBasedIntToRefDictionary.java	89.34% -4.08%	🍏
AbstractMutableArray.java	79.02% -5.59%	❌