feat(#446): plugins tab full parity — install from URL, provider selection, remove confirm, badges (#456)

* docs: document HermesScaffold padding foot-gun root cause in AGENTS.md

* feat(#446): plugins tab full parity — install from URL, provider selection, remove confirm, badges

- Add Install from URL section with force reinstall + enable after install toggles
- Add Plugin Provider selection section (memory provider + context engine dropdowns)
- Add rescan button in top bar actions
- Add confirmation dialog before removing plugins
- Show source badges, runtime status, auth badges on plugin cards
- Show dashboard slots from plugin manifest
- Add visibility toggle (show/hide in sidebar) for manifest plugins
- Show orphan dashboard plugins section
- Add PluginManifestData, PluginsHubProviders, ProviderOption models
- Add rescanPlugins, savePluginProviders, setPluginVisibility API endpoints

* fix(#446): fix CI compilation errors — DashboardPluginMeta mapping and @Composable context

* fix(#446): pass missing PluginInfo ctor params for orphan plugin mapping

* fix(#446): remove duplicate refresh button in plugins top bar

Scaffold's onRefresh param added a second refresh icon alongside the
rescan action button. Removed onRefresh/isRefreshing from HermesScaffold
and moved pull-to-refresh into a manual PullToRefreshBox wrapping the
content, keeping the rescan icon as the sole top-bar action.

* fix(#446): remove rescan icon from plugins top bar

Only one action icon left in top bar; pull-to-refresh (loadPlugins)
remains the sole refresh mechanism. rescanPlugins() viewmodel logic
is unchanged but now unreachable from the UI.

---------

Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/data/model/PluginInfo.kt

@@ -9,6 +9,7 @@ data class PluginInfo(
     val source: String?,
     @SerializedName("runtime_status") val runtimeStatus: String?,
     @SerializedName("has_dashboard_manifest") val hasDashboardManifest: Boolean = false,
+    @SerializedName("dashboard_manifest") val dashboardManifest: PluginManifestData? = null,
     @SerializedName("can_remove") val canRemove: Boolean = false,
     @SerializedName("can_update_git") val canUpdateGit: Boolean = false,
     @SerializedName("auth_required") val authRequired: Boolean = false,
@@ -24,8 +25,50 @@ data class PluginInfo(
                 runtimeStatus.equals("disabled", ignoreCase = true)
 }
 
+data class PluginManifestData(
+    val name: String? = null,
+    val label: String? = null,
+    val description: String? = null,
+    val icon: String? = null,
+    val version: String? = null,
+    val tab: PluginTabInfo? = null,
+    val slots: List<String>? = null,
+    val entry: String? = null,
+    val css: String? = null,
+    @SerializedName("has_api") val hasApi: Boolean = false,
+    val source: String? = null,
+)
+
+data class PluginTabInfo(
+    val path: String? = null,
+    val position: String? = null,
+    val override: String? = null,
+    val hidden: Boolean = false,
+)
+
+data class DashboardPluginMeta(
+    val name: String? = null,
+    val label: String? = null,
+    val description: String? = null,
+    val tab: PluginTabInfo? = null,
+)
+
+data class PluginsHubProviders(
+    @SerializedName("memory_provider") val memoryProvider: String? = null,
+    @SerializedName("memory_options") val memoryOptions: List<ProviderOption> = emptyList(),
+    @SerializedName("context_engine") val contextEngine: String? = null,
+    @SerializedName("context_options") val contextOptions: List<ProviderOption> = emptyList(),
+)
+
+data class ProviderOption(
+    val name: String,
+    val description: String? = null,
+)
+
 data class PluginsHubResponse(
     val plugins: List<PluginInfo>,
+    @SerializedName("orphan_dashboard_plugins") val orphanDashboardPlugins: List<DashboardPluginMeta> = emptyList(),
+    val providers: PluginsHubProviders? = null,
 )
 
 data class AgentPluginInstallBody(
@@ -33,3 +76,8 @@ data class AgentPluginInstallBody(
     val force: Boolean = false,
     val enable: Boolean = true,
 )
+
+data class PluginProvidersPutRequest(
+    @SerializedName("memory_provider") val memoryProvider: String? = null,
+    @SerializedName("context_engine") val contextEngine: String? = null,
+)