fix: nango watermark can't be turned off in self hosted

[ej-sanmartin]

Describe

#4750 didn't surface watermark disabling and enabling in frontend, where it was previously just checking if user has a plan. Now, frontend has similar checks with backend https://github.com/NangoHQ/nango/blob/master/packages/shared/lib/services/connect-ui-settings.service.ts#L94-L100 when it comes to enabling / disabling Nango watermark in settings.

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Issue

Fixes #4915

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Testing

• Ran locally in docker
• Vid Demo of Self Hosted Enabling Watermark Removal

Screen.Recording.2025-11-19.at.7.04.09.PM.mov

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Expose hosting flags & unify watermark-disable logic

Adds isHosted and isEnterprise flags to the env JS payload and propagates them through shared types. Front-end settings page now mirrors the back-end rule for deciding whether the Connect UI watermark can be disabled, fixing the inability to remove the watermark in self-hosted deployments. Tooltip copy is updated to provide context-specific guidance.

Key Changes

• Updated packages/server/lib/controllers/v1/getEnvJs.ts to append isHosted and isEnterprise to window._env and include them in the features object returned to the browser
• Extended WindowEnv interface in packages/types/lib/web/env.ts with isHosted and isEnterprise booleans
• Refactored packages/webapp/src/pages/Environment/Settings/ConnectUISettings/index.tsx to compute canDisableWatermark using globalEnv flags and environment plan; switch disabled state and tooltip message now conditional on the new logic

Affected Areas

• getEnvJs controller (env JS generation)
• WindowEnv shared type
• Connect UI settings React component

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This summary was automatically generated by @propel-code-bot

[kaposke]

LGTM, thanks for contributing :)

[ej-sanmartin]

Ran eslint to fix linting errors.