chore: remove dead permission details code (#38606)

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## **Description**

Removes the following dead code:
- permission-details-modal
- connection-list-tooltitp
- connections route


Trace:
1. Connections route is unused
2. This was the only code path that set menuType Connection, therefore
ConnectedAccountsMenu is also unused
3. In turn, this made PermissionDetailsModal unused

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## **Changelog**

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## **Related issues**

Fixes:

## **Manual testing steps**

N/A

## **Screenshots/Recordings**

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### **Before**

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### **After**

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## **Pre-merge author checklist**

- [ ] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [ ] I've completed the PR template to the best of my ability
- [ ] I’ve included tests if applicable
- [ ] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
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Not required for external contributors.

## **Pre-merge reviewer checklist**

- [ ] I've manually tested the PR (e.g. pull and build branch, run the
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- [ ] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.



<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Removes the unused Connections flow and related
components/routes/tests/styles, and prunes associated i18n strings.
> 
> - **Routing/Navigation**:
> - Remove `CONNECTIONS` constant, route definitions, and lazy import;
clean up route utils to stop special-casing Connections.
> - **Multichain UI**:
>   - Delete `Connections` page and associated tests/snapshots/styles.
> - Remove `ConnectedAccountsMenu` and `PermissionDetailsModal`
components (stories, tests, types, styles, exports) and their usage from
`AccountListItem`.
> - Simplify `account-list-item`: drop `Connection` menu type and
related props (`accountsCount`, `onActionClick`).
> - Replace CSS height with `h-full` in no-connection content; remove
connections SCSS import.
> - **Permissions Page**:
>   - Remove `connection-list-tooltip` component and story.
> - **I18n**:
> - Prune unused messages across locales (e.g., `connectedAccounts`,
`connectedAccountsToast`, `disconnectedAllAccountsToast`,
`disconnectedSingleAccountToast`, `permissionDetails`, `plusMore`).
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
5f24278. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: n3ps