fix(many): form components do not take up full width in slot (#27306)

Issue number: resolves #27305

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## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->

Checkbox, radio, range, select, and toggle take up 100% of its width
even when in a start/end slot.

## What is the new behavior?
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this PR. -->

- Checkbox, radio, range, select, and toggle do not take up 100% of its
width even when in a start/end slot.
. The "no slot" behavior is unchanged and aligns with the legacy select.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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and migration path for existing applications below. -->


## Other information

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screenshots of how the component looks before and after the change. -->

core/src/components/checkbox/checkbox.scss

@@ -42,8 +42,14 @@
   height: 100%;
 }
 
-:host(.in-item[slot="start"]:not(.legacy-checkbox)),
-:host(.in-item[slot="end"]:not(.legacy-checkbox)) {
+/**
+ * Checkbox can be slotted
+ * in components such as item and
+ * toolbar which is why we do not
+ * limit the below behavior to just ion-item.
+ */
+:host([slot="start"]:not(.legacy-checkbox)),
+:host([slot="end"]:not(.legacy-checkbox)) {
   width: auto;
 }