feat: implement Phase 1 MVP of Implausibly

Working Android dashboard app for self-hosted Plausible Analytics CE.
Connects to Plausible API v2 (POST /api/v2/query), displays top stats,
visitor chart, top sources, and top pages with date range selection.

Architecture: Kotlin + Jetpack Compose + Material 3 + Hilt + Ktor +
SQLDelight + EncryptedSharedPreferences. Single :app module, four-layer
unidirectional data flow (UI → ViewModel → Repository → Data).

Includes: instance management, site list, caching with TTL per date
range, encrypted API key storage, custom Canvas visitor chart,
pull-to-refresh, and unit tests for API, cache, repository, and
domain model layers.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/proguard-rules.pro

@@ -0,0 +1,27 @@
+# SPDX-License-Identifier: GPL-3.0-only
+
+# kotlinx.serialization
+-keepattributes *Annotation*, InnerClasses
+-dontnote kotlinx.serialization.AnnotationsKt
+
+-keepclassmembers class kotlinx.serialization.json.** {
+    *** Companion;
+}
+-keepclasseswithmembers class kotlinx.serialization.json.** {
+    kotlinx.serialization.KSerializer serializer(...);
+}
+
+-keep,includedescriptorclasses class no.naiv.implausibly.**$$serializer { *; }
+-keepclassmembers class no.naiv.implausibly.** {
+    *** Companion;
+}
+-keepclasseswithmembers class no.naiv.implausibly.** {
+    kotlinx.serialization.KSerializer serializer(...);
+}
+
+# Ktor
+-keep class io.ktor.** { *; }
+-dontwarn io.ktor.**
+
+# SQLDelight
+-keep class app.cash.sqldelight.** { *; }