refactor(scheduler): remove redundant sorting

[skirtles-code]

Note: This PR currently contains all the changes from #7746. I think that PR should be merged first. This PR is much simpler than it looks, but I needed the code from that PR to avoid breaking the tests.

To understand the refactoring I've done here, see commit fed5518.

---

Currently, we sort scheduler jobs twice in the main scheduler queue:

1. In queueJob/findInsertionIndex we calculate where to insert new jobs, ensuring the queue is correctly sorted.
2. In flushJobs we sort the queue again.

This second sort shouldn't be needed, as the jobs should already be sorted. Its extra code and extra work. It can also lead to inconsistencies and bugs when the two sorts don't perfectly align.

This PR removes that second sort.

This caused a few test failures. Those failures had two underlying causes:

1. The bug fixed by fix(runtime-core): pre jobs without an id should run first #7746. The extra sort was hiding the problem from the existing tests. I've included the changes from that PR in this PR, but they aren't really part of this refactoring. I think that PR should be merged first, fixing the bug, separately from this refactoring.
2. There was a bug in findInsertionIndex. The value of start needs to be 0 when isFlushing is false, but it was being set to 1 instead. This bug didn't impact users because the sort in flushJobs was correcting the order. Now the second sort is removed it needs to be handled directly in findInsertionIndex.

With those problems addressed, the existing tests all pass.

[github-actions]

Size Report

Bundles

File	Size	Gzip	Brotli
runtime-dom.global.prod.js	98.6 kB (-121 B)	37.4 kB (-32 B)	33.6 kB (-41 B)
vue.global.prod.js	156 kB (-121 B)	57.2 kB (-41 B)	50.9 kB (-1 B)

Usages

Name	Size	Gzip	Brotli
createApp	54 kB (-121 B)	20.9 kB (-44 B)	19.1 kB (-83 B)
createSSRApp	58 kB (-121 B)	22.6 kB (-49 B)	20.6 kB (-52 B)
defineCustomElement	58.7 kB (-121 B)	22.4 kB (-38 B)	20.5 kB (+8 B)
overall	67.6 kB (-121 B)	26 kB (-28 B)	23.7 kB (-22 B)

[pkg-pr-new]

commit: 57a350b

@vue/compiler-core

pnpm add https://pkg.pr.new/@vue/compiler-core@11646

@vue/compiler-dom

pnpm add https://pkg.pr.new/@vue/compiler-dom@11646

@vue/compiler-sfc

pnpm add https://pkg.pr.new/@vue/compiler-sfc@11646

@vue/compiler-ssr

pnpm add https://pkg.pr.new/@vue/compiler-ssr@11646

@vue/reactivity

pnpm add https://pkg.pr.new/@vue/reactivity@11646

@vue/runtime-core

pnpm add https://pkg.pr.new/@vue/runtime-core@11646

@vue/runtime-dom

pnpm add https://pkg.pr.new/@vue/runtime-dom@11646

@vue/server-renderer

pnpm add https://pkg.pr.new/@vue/server-renderer@11646

@vue/shared

pnpm add https://pkg.pr.new/@vue/shared@11646

vue

pnpm add https://pkg.pr.new/vue@11646

@vue/compat

pnpm add https://pkg.pr.new/@vue/compat@11646

Open in Stackblitz

[yyx990803]

/ecosystem-ci run

[vue-bot]

📝 Ran ecosystem CI: Open

suite	result	latest scheduled
language-tools	❌ failure	❌ failure
nuxt	✅ success	✅ success
pinia	✅ success	✅ success
primevue	✅ success	✅ success
quasar	✅ success	✅ success
radix-vue	✅ success	✅ success
router	✅ success	✅ success
test-utils	✅ success	✅ success
vant	✅ success	✅ success
vite-plugin-vue	✅ success	✅ success
vitepress	✅ success	✅ success
vue-i18n	✅ success	✅ success
vue-macros	✅ success	✅ success
vuetify	✅ success	✅ success
vueuse	✅ success	✅ success
vue-simple-compiler	✅ success	✅ success