build(jacoco): scope the fail-closed encryption UI out of the JVM coverage surface (#359)

CacheEncryptionGate.kt (the gate composable, blank cover, error screen, and ephemeral
report-review screen added for #359) is pure Compose render code, structurally
unreachable from a JVM unit test the same way every other Screen file in
jacocoNonJvmTestableSurface is. Left in scope, it dragged the whole-app line ratio to
0.78, just under the 0.79 no-regression floor.

Excluded it via "**/CacheEncryptionGateKt*" rather than the usual bare
"**/CacheEncryptionGate*" pattern this list otherwise uses, because
CacheEncryptionGateViewModel is named with "CacheEncryptionGate" as a literal
prefix - the bare wildcard would also have swallowed the already JVM-tested,
94%-covered ViewModel and its sealed CacheEncryptionGateState. CacheEncryptionGateViewModel
and CacheEncryptionUnavailableException stay in scope unchanged.

Verified locally: testDebugUnitTest + jacocoTestCoverageVerification now pass, with
the line ratio recovered to about 0.807 (5,044 covered / 6,249 total lines) - the
same 5,044 covered lines as before, just a smaller, honestly-JVM-testable denominator.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/build.gradle.kts

@@ -311,6 +311,15 @@ val jacocoNonJvmTestableSurface = listOf(
     "**/SettingsComponents*",
     "**/SignatureEditScreen*",
     "**/SignaturesScreen*",
+    // CacheEncryptionGate.kt (issue #359/#367 fail-closed encryption gate) is pure render: the gate
+    // composable, its blank cover, the error screen, and the ephemeral report-review screen — no plain
+    // top-level logic. Spelled out to "...GateKt*" (the file's compiled facade class), NOT the bare
+    // "**/CacheEncryptionGate*" this list otherwise uses, because unlike every Screen/ViewModel pair
+    // above, CacheEncryptionGateViewModel's name literally starts with "CacheEncryptionGate" — a bare
+    // wildcard would also swallow the (94%-covered, dedicated-tested) ViewModel and its sealed
+    // CacheEncryptionGateState. CacheEncryptionGateViewModel and CacheEncryptionUnavailableException
+    // stay in scope (both have JVM tests: CacheEncryptionGateViewModelTest, DatabaseProvisionerTest).
+    "**/CacheEncryptionGateKt*",
     // --- Android framework entry points (OS-instantiated). NB: Workers are intentionally NOT here
     // --- (they are unit-tested — see the KEPT IN SCOPE note above).
     "**/*Activity*",