feat(apps): let front components open a record in the side panel (#22140)

## Why

Front components (apps) could `navigate()` to a record's **full page**,
but there was no way to open a specific record in the **side panel**.
More generally, `openSidePanelPage` could navigate to a `SidePanelPages`
enum page but couldn't pass the context most pages need.

## What

`openSidePanelPage`'s params are now a **discriminated union keyed on
`page`**, so each page declares its own typed payload (instead of a flat
bag of optionals whose validity silently depends on `page`). This is
also safer: pages that can't render without context can't be "opened"
into a broken panel.

Wired the param-bearing pages host-side, each bridging to its existing
internal hook:

| `page` | Params | Bridges to |
|---|---|---|
| `ViewRecord` | `recordId`, `objectNameSingular`,
`resetNavigationStack?` | `useOpenRecordInSidePanel` (full-page fallback
on mobile / unsupported objects) |
| `EditRichText` | `recordId`, `objectNameSingular`, `fieldName?` |
`useOpenRichTextInSidePanel` |
| `ComposeEmail` | `connectedAccountId`, `threadId?`, `defaultTo?`,
`defaultSubject?`, `defaultInReplyTo?`, `pageTitle?`, `pageIcon?` |
`useOpenComposeEmailInSidePanel` |
| `ViewFrontComponent` | `frontComponentId`, optional
`recordId`+`objectNameSingular`, `pageTitle`, `pageIcon?`,
`resetNavigationStack?` | `useOpenFrontComponentInSidePanel` |
| *(any other page)* | `pageTitle`, `pageIcon?`,
`shouldResetSearchState?` | `navigateSidePanel` |

`CommandOpenSidePanelPage` now takes the union directly, so headless
command-menu items can open any of these. Threaded through `twenty-sdk`
→ `twenty-front-component-renderer` → host
(`useFrontComponentExecutionContext`), with unit tests per page and the
mobile/unsupported fallbacks.

## Deliberately deferred: `MergeRecords`

`useOpenMergeRecordsPageInSidePanel` takes `objectNameSingular` /
`objectRecordIds` at **hook-init** (it calls `useObjectMetadataItem` /
`useLazyFindManyRecords` at render), so it can't be driven by runtime
app params without refactoring that hook + its current caller. Left out
of this PR — better as its own change.

## Worth a second look (reviewers)

- **`ViewFrontComponent`** lets an app open a front component by id.
Within an app that's clean composition; whether an app should be able to
target *another* app's component is a scoping/security question. The
render still runs under the app's access token, so cross-app fetches
would fail auth — but flagging it explicitly.

## Security note

Side-panel record/page views render natively under the **user's**
session/Apollo client, not the app's scoped token — RLS/field
permissions are enforced as if the user opened it themselves. Same trust
model as `navigate(AppPath.RecordShowPage, …)`.

## Follow-up

A separate PR will centralize the mobile + `canOpenObjectInSidePanel`
guard inside `useOpenRecordInSidePanel` (currently duplicated across
callers, missing in others).

## Validation

> [!NOTE]
> Dependencies wouldn't install in this environment (flaky network
during `yarn install`), so lint / typecheck / jest weren't run locally —
relying on CI. The diff was reviewed manually for type-consistency,
including the discriminated-union narrowing in the host switch.

https://claude.ai/code/session_01AAJFXzsCeoj6BeP3ofiTKQ

packages/twenty-docs/developers/extend/apps/layout/front-components.mdx

@@ -121,7 +121,7 @@ Import them from `twenty-sdk/command`:
 - **`Command`** — Runs an async callback via the `execute` prop.
 - **`CommandLink`** — Navigates to an app path. Props: `to`, `params`, `queryParams`, `options`.
 - **`CommandModal`** — Opens a confirmation modal. If the user confirms, executes the `execute` callback. Props: `title`, `subtitle`, `execute`, `confirmButtonText`, `confirmButtonAccent`.
-- **`CommandOpenSidePanelPage`** — Opens a specific side panel page. Props: `page`, `pageTitle`, `pageIcon`.
+- **`CommandOpenSidePanelPage`** — Opens a side panel page. Props depend on `page` — e.g. `ViewRecord` takes `recordId` + `objectNameSingular`, other pages take `pageTitle` + `pageIcon`.
 
 Here is a full example of a headless front component using `Command` to run an action from the command menu:
 
@@ -381,7 +381,7 @@ The following system variables are always available via `process.env`:
 
 | Variable | Description |
 |----------|-------------|
-| `TWENTY_FUNCTIONS_URL` | Base URL your app's HTTP logic functions are served from (used by `RestApiClient`) |
+| `TWENTY_FUNCTIONS_URL` | Base URL your app's HTTP logic functions are served from |
 | `TWENTY_API_URL` | Base URL of the Twenty core API |
 | `TWENTY_APP_ACCESS_TOKEN` | Short-lived token scoped to your app's role |