feat(enterprise): whitelabeling sections, SSO controls & license gating

[imrja8]

What is this PR about?

Adds enterprise whitelabeling controls, SSO/sidebar feature toggles, self-hosted restrictions, and full license-based gating — all scoped to self-hosted instances with an active enterprise license.

Whitelabeling (Branding)

• Server-renders title, favicon (inlined as base64 data URI), custom CSS, and full OG/Twitter meta tags in _document to eliminate the flash of default Dokploy branding on first paint
• Adds metaDescription and ogImageUrl fields for social link previews
• Adds per-section enable switches (Branding, Metadata & Links, Error Pages, Forgot Password, Appearance) — disabled sections hide their fields in the UI and are not applied to the app
• Adds a Forgot Password section: admin can set a password reset guide + support email; when configured, the login page's "Lost your password?" link shows the guide and a "Get Support" mailto button instead of linking to the Dokploy docs
• SSR-prefetches public branding on login/register so logo and app name render on first paint without a flash
• Removes the client-side WhitelabelingProvider (title/favicon/CSS now server-rendered)

SSO / Restrictions

• Adds Hide Help Links, Hide Social Links, Hide SSO Login toggles
• Moves Self-hosted Restrictions from the SSO page to the License page
• Adds Feature switches on the License page to show/hide SSO and Whitelabeling in the sidebar

License gating

• All enterprise features (whitelabeling, SSO, restrictions) are automatically treated as off when the license is inactive or enterprise is not enabled (hasValidLicenseForInstance)
• Default state is off for all new fields — existing installs are unaffected until an admin explicitly enables each section

Sidebar

• Reduces expanded sidebar width and prevents horizontal scroll when collapsed
• Org name in the header now truncates instead of wrapping at narrower widths

Database

• Migrations 0173–0179 add new webServerSettings columns and whitelabelingConfig keys — auto-applied on setup/start, no manual DB action needed

Checklist

• Created a dedicated branch based on canary
• Read CONTRIBUTING.md
• Tested in local instance — all features verified end-to-end (SSR output confirmed via curl, DB state, both enable/disable directions)

Issues related (if applicable)

N/A

Screenshots (if applicable)

N/A