Local Network Access permission storage + `permissions.query()`

Component: WebKit NetworkProcess | f83ad9a

Local Network Access (LNA) restricts pages from reaching local/loopback resources without a user-granted permission. The decision is enforced in NetworkProcess, but navigator.permissions.query() is normally answered by the UI process. This commit adds NetworkProcess-side storage for LNA grants/denials, a revocation path, and permissions.query() support for 'local-network'/'loopback-network'. Previously the check algorithm consulted a grant map nothing ever wrote to, so decisions were unreachable.

Significance

LNA's permission model becomes functional for the first time, with the authoritative answer moved into the process that enforces it — closing a gap where a page could be told 'granted' while access was actually refused. WebPermissionController special-cases the two names so the web process routes the query directly to NetworkProcess. Decisions are keyed by both requesting and top-level origin, and tracked as two distinct permissions rather than one combined state (unlike Chromium's pre-split model).

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