feat(collection): support `findLast` and `reduceRight` methods

[jaw0r3k]

Please describe the changes this PR makes and why it should be merged:

🤖 Generated by Copilot at 9150f28

This pull request enhances the Collection class with new methods that mirror the Array class. These methods provide more options for working with collections of data, such as finding the last element that matches a predicate or applying a function from right to left. The new methods are implemented in packages/collection/src/collection.ts.

• Add findLast and findLastKey methods to Collection class to search for the last item or key that satisfies a predicate function (link)
• Add reduceRight method to Collection class to apply a function to each item of the collection from the last one and accumulate a single value (link)

Status and versioning classification:

• I know how to update typings and have done so, or typings don't need updating
• This PR changes the library's interface (methods or parameters added)

[vercel[bot]]

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[codecov[bot]]

Codecov Report

Merging #9573 (5fd2bdc) into main (c051ed9) will increase coverage by 0.21%. The diff coverage is 93.25%.

@@            Coverage Diff             @@
##             main    #9573      +/-   ##
==========================================
+ Coverage   60.04%   60.26%   +0.21%     
==========================================
  Files         235      235              
  Lines       16025    16105      +80     
  Branches     1216     1231      +15     
==========================================
+ Hits         9622     9705      +83     
+ Misses       6359     6356       -3     
  Partials       44       44              

Flag	Coverage Δ
collection	99.23% <93.25%> (-0.64%)	:arrow_down:
next	∅ <ø> (∅)
proxy	75.00% <ø> (ø)
rest	92.77% <ø> (ø)
ws	52.63% <ø> (ø)

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Files	Coverage Δ
packages/collection/src/collection.ts	99.23% <93.25%> (-0.64%)	:arrow_down:

... and 1 file with indirect coverage changes

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[ImRodry]

I know this isn't in the ES2023 spec but would there be room to add a getLast?

[jaw0r3k]

there already is last() method @ImRodry

[github-actions[bot]]

⚡️ Lighthouse report for the changes in this PR:

Category	Score
🟢 Performance	100
🟢 Accessibility	100
🟢 Best practices	92
🟢 SEO	92
🟠 PWA	67

Lighthouse ran on https://discord-js-git-fork-jaw0r3k-findlast-discordjs.vercel.app/