refactor: migrate remaining Vue components to <script setup> (#38752)

Migrates the last four Options API components, so all 20 `.vue` files
now use `<script setup>`, and disables the Vue Options API runtime. This
will enable optimizations like Vue Vapor mode in the future.

Bug fixes done while migrating and testing:

- Branch selector: arrowing onto "Create branch …" threw a `TypeError`,
and Enter on it did nothing
- Dashboard: the search term was not escaped, so `&` injected query
parameters and `#` truncated the request
- Dashboard: an unknown `repo-search-filter` threw, and names like
`constructor` leaked `Object.prototype` members into the request
- Dashboard: an unknown archived/private filter rendered `function
Object() { [native code] }` as a checkbox tooltip
- Dashboard: removed a dropdown init that always ran against a
not-yet-rendered element
- Branch selector: the `document.body` click listener was never removed
on unmount
- Contributors: the chart plugin relied on an undeclared chart.js field
- Contributors: `contributorsStats` was mutated behind a `shallowRef`,
so future readers would not update
- Removed template attributes and pageData keys that no component had
read for years

---------

Signed-off-by: silverwind <me@silverwind.io>

templates/repo/branch_dropdown.tmpl

@@ -16,7 +16,6 @@ Search "repo/branch_dropdown" in the template directory to find all occurrences.
 */}}
 <div class="{{if .ContainerClasses}}{{.ContainerClasses}}{{end}}"
 	data-global-init="initRepoBranchTagSelector"
-	data-text-release-compare="{{ctx.Locale.Tr "repo.release.compare"}}"
 	data-text-branches="{{ctx.Locale.Tr "repo.branches"}}"
 	data-text-tags="{{ctx.Locale.Tr "repo.tags"}}"
 	data-text-filter-branch="{{ctx.Locale.Tr "repo.pulls.filter_branch"}}"

templates/user/dashboard/repolist.tmpl

@@ -3,9 +3,6 @@ const data = {
 	...window.config.pageData.dashboardRepoList, // it only contains searchLimit and uid
 
 	isMirrorsEnabled: {{.MirrorsEnabled}},
-	isStarsEnabled: {{not .IsDisableStars}},
-
-	canCreateMigrations: {{not .DisableMigrations}},
 
 	textNoOrg: {{ctx.Locale.Tr "home.empty_org"}},
 	textNoRepo: {{ctx.Locale.Tr "home.empty_repo"}},