fix(item, tab-button): activation behaviour for Ionic theme (#30806)

Issue number: resolves #

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## What is the current behavior?
Currently, in the`ion-item` and `tab-button` components under the Ionic
theme, activation behaviors (such as ripple effects and clickability)
are applied to both `md` and `ios`, but they should only be applied
to`md`.

## What is the new behavior?
Activation behavior is now conditional on both theme and mode. The main
goal is to ensure that activation only occurs specifically for `md` mode
when using the `ionic` theme.


## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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