Maintenance: Consolidate useMergedRef and convert to typescript

[MikesGlitch]

Consolidate useMergedRefs hook and convert it to TypeScript.

Relates to : #1483

[netlify]

✅ Deploy Preview for actualbudget ready!

Name	Link
🔨 Latest commit	da5849e
🔍 Latest deploy log	https://app.netlify.com/sites/actualbudget/deploys/65106326cc2843000876605c
😎 Deploy Preview	https://deploy-preview-1733.demo.actualbudget.org/
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[github-actions]

Bundle Stats — desktop-client

Hey there, this message comes from a GitHub action that helps you and reviewers to understand how these changes affect the size of this project's bundle.

As this PR is updated, I'll keep you updated on how the bundle size is impacted.

Total

Files count	Total bundle size	% Changed
16	2.48 MB → 2.48 MB (-28 B)	-0.00%

Changeset

File	Δ	Size
src/hooks/useMergedRefs.ts	🆕 +494 B	0 B → 494 B
src/components/sort.tsx	📉 -407 B (-10.94%)	3.63 kB → 3.23 kB
src/hooks/useMergedRefs.js	🔥 -494 B (-100%)	494 B → 0 B

View detailed bundle breakdown

Added

No assets were added

Removed

No assets were removed

Bigger

Asset	File Size	% Changed
static/js/main.js	1.11 MB → 1.12 MB (+105 B)	+0.01%

Smaller

Asset	File Size	% Changed
static/js/wide-components.chunk.js	126.98 kB → 126.85 kB (-133 B)	-0.10%

Unchanged

Asset	File Size	% Changed
static/js/678.chunk.js	420.74 kB	0%
static/media/Inter-italic.var.woff2	239.29 kB	0%
static/media/Inter-roman.var.woff2	221.86 kB	0%
static/js/713.chunk.js	156.56 kB	0%
static/js/231.chunk.js	117.37 kB	0%
static/js/narrow-components.chunk.js	35.15 kB	0%
static/js/reports.chunk.js	29.23 kB	0%
static/js/473.chunk.js	13 kB	0%
static/js/389.chunk.js	12.76 kB	0%
static/js/resize-observer-polyfill.chunk.js	8.88 kB	0%
static/css/main.css	7.41 kB	0%
asset-manifest.json	2.07 kB	0%
index.html	1.66 kB	0%
static/media/browser-server.js	903 B	0%

[github-actions]

Bundle Stats — loot-core

Hey there, this message comes from a GitHub action that helps you and reviewers to understand how these changes affect the size of this project's bundle.

As this PR is updated, I'll keep you updated on how the bundle size is impacted.

Total

Files count	Total bundle size	% Changed
2	2.22 MB	0%

Changeset

No files were changed

View detailed bundle breakdown

Added

No assets were added

Removed

No assets were removed

Bigger

No assets were bigger

Smaller

No assets were smaller

Unchanged

Asset	File Size	% Changed
kcab.worker.js	1.23 MB	0%
xfo.xfo.kcab.worker.js	1014.46 kB	0%

[MatissJanis]

Perfect! Thank you so much!

(we're currently in merge freeze which means only bugfixes and low-risk changes are merged; I would argue this qualifies as "low-risk" change, so I'll go ahead and merge it now)