feat(ionic-theme): improve scss architecture for ionic theme (#29345)

Issue number: None

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## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

This PR follows the architectural changes defined on the _SCSS
Architecture Design Doc_. Due to some of the developments done in the
meantime, not everything that was defined on that document was followed
and some sections were simplified.

Overall, there were two guidelines that supported the work on this PR:
- Have no impact on the current scss partials & CSS architecture for the
`md/iOS` themes.
- Make everything related to the new `Ionic` Theme separated.

Based on these, here're the changes made:

**On Themes folder (private):**
- Renamed current internal scss partials on src/themes, related to
md/iOS, to `native.*.scss` and move them to a new folder, called
`native`. Updated imports on all framework.
- Removed the ionic prefix from the name of the mixins and function
partials on src/themes. Updated imports on all framework.
- Created new folder, named ionic, inside src/themes. This holds the
`ionic.globals.scss`, with all the mixins and functions forwarded, to be
used on other scopes.
- Replaced on already created Ionic theme files, the usage of tokens and
mixins with @use, to instead _@use
"../../themes/ionic/ionic.globals.scss" as globals;_. This ensures an
equal approach is followed everywhere and also makes it easier to change
the files imported or paths, in the future, as its all in the same
global file.
- Updated the foundations `readMe` file, with the new process for using
globals.


![themes](https://github.com/ionic-team/ionic-framework/assets/32780808/1455523c-3ccd-4310-a974-522f9f8ade02)


**On css folder (public):**
- Created new folder, named `ionic`, inside src/css. This holds all the
files related exclusively to Ionic Theme, following the same structure
as exists now for md/iOS, with a core, a bundle, utils, etc. Some files
were a bit duplicated, to eliminate imports from ios or md theme
partials. The only file common to both Themes is the `normalize.scss`.
- No folder structure or renamings were done on the existing output, to
prevent breaking-changes for developers already making imports from this
folder.
- Updated typography and link partials to use globals instead of tokens.
- Changed `font-size` styles on typography to be on `body`, instead of
`html`, to enable correct support of accessibility features on browsers
and devices, related to `font-size`.


![css](https://github.com/ionic-team/ionic-framework/assets/32780808/10bedddc-23c1-4c50-a4e4-77fb7f6c6430)


**Other changes related to global styles new architecture:**
- Updated margin & padding utility-classed generated by token, to
include css variables and padding/margin mixins.
- Updated link test to use new global Ionic bundle, correct
utility-class on ion-content and updated snapshots. The font-size
changed to 16, as its now the default on the body.
- Updated typography snapshots.
- Updated prettier format on all scss files. Later on we should make
sure this is equal for all team members.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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---------

Co-authored-by: Sean Perkins <sean@ionic.io>

packages/vue/src/vue-component-lib/utils.ts

@@ -91,8 +91,17 @@ export const defineContainer = <Props, VModelType = string | number | boolean>(
         const eventsNames = Array.isArray(modelUpdateEvent) ? modelUpdateEvent : [modelUpdateEvent];
         eventsNames.forEach((eventName: string) => {
           el.addEventListener(eventName.toLowerCase(), (e: Event) => {
-            modelPropValue = (e?.target as any)[modelProp];
-            emit(UPDATE_VALUE_EVENT, modelPropValue);
+            /**
+             * Only update the v-model binding if the event's target is the element we are
+             * listening on. For example, Component A could emit ionChange, but it could also
+             * have a descendant Component B that also emits ionChange. We only want to update
+             * the v-model for Component A when ionChange originates from that element and not
+             * when ionChange bubbles up from Component B.
+             */
+            if (e.target.tagName === el.tagName) {
+              modelPropValue = (e?.target as any)[modelProp];
+              emit(UPDATE_VALUE_EVENT, modelPropValue);
+            }
           });
         });
       },