fix(native): render plan proposals inline

Render ExitPlanMode and exit_plan_mode Markdown from input.plan in iOS and Android conversations. Preserve approvals, raw source and diagnostics while hiding empty output placeholders and prewarming plan documents.

Add generated protocol fixtures and native regression coverage for long plans, live updates, recycling, themes and typography.

android/app/src/main/kotlin/app/hapi/companion/feature/chat/ChatViewModel.kt

@@ -2,6 +2,7 @@ package app.hapi.companion.feature.chat
 
 import androidx.annotation.MainThread
 import app.hapi.companion.feature.chat.attachments.ComposerAttachments
+import app.hapi.companion.feature.chat.blocks.planProposalMarkdown
 import app.hapi.companion.feature.chat.composer.ChatDrafts
 import app.hapi.companion.feature.chat.composer.SlashCommands
 import app.hapi.companion.feature.chat.composer.appendTranscript
@@ -31,6 +32,7 @@ import app.hapi.protocol.catalog.PermissionMode
 import app.hapi.protocol.catalog.PermissionModes
 import app.hapi.protocol.chat.NormalizedMessage
 import app.hapi.protocol.chat.ToolGroupBlock
+import app.hapi.protocol.chat.ToolCallBlock
 import app.hapi.protocol.chat.ToolGroupingOptions
 import app.hapi.protocol.chat.VisibleChatBlock
 import app.hapi.protocol.chat.buildVisibleChatBlocks
@@ -1671,6 +1673,7 @@ class ChatViewModel(
             when (block) {
                 is AgentTextBlock -> block.text
                 is AgentReasoningBlock -> block.text
+                is ToolCallBlock -> planProposalMarkdown(block.tool)
                 else -> null
             }
         }.toSet()

android/app/src/main/kotlin/app/hapi/companion/feature/chat/blocks/ToolBodies.kt

@@ -46,16 +46,22 @@ import kotlinx.serialization.json.JsonPrimitive
  * - `Write` → the written content as a code block;
  * - `CodexDiff` (and any input/result that parses as a unified diff) → [DiffView];
  * - `TodoWrite`/`update_plan` → checklist rows;
+ * - `ExitPlanMode`/`exit_plan_mode` → complete Markdown proposal from input;
  * - Ask/RequestUserInput → questions + selected answers, read-only;
  * - anything else → pretty-printed JSON input, then the generic result.
  */
 @Composable
 internal fun ToolCallBody(tool: ChatToolCall, basePath: String?, modifier: Modifier = Modifier) {
     val questionTool = isQuestionDetailsTool(tool.name)
+    val plan = planProposalMarkdown(tool)
     val answers = if (questionTool) tool.permission?.answers else null
     Column(modifier = modifier, verticalArrangement = Arrangement.spacedBy(8.dp)) {
         if (questionTool) {
             QuestionToolBody(tool)
+        } else if (plan != null) {
+            // Plans are reading documents, never paged/truncated tool source.
+            Markdown(text = plan)
+            if (planProposalShowsResult(tool)) ToolResultSection(tool)
         } else {
             SectionLabel(stringResource(R.string.settings_usage_input))
             ToolInputSection(tool)

android/app/src/main/kotlin/app/hapi/companion/feature/chat/blocks/ToolCallBlockView.kt

@@ -51,8 +51,8 @@ import kotlinx.serialization.json.JsonPrimitive
  * One tool invocation (web `ToolCard`): collapsed header row — icon glyph,
  * title, subtitle, status — expanding to the per-tool body ([ToolCallBody]),
  * the read-only permission state, and nested children (sidechain transcript).
- * Cards with a pending permission start expanded and carry the
- * "awaiting approval" banner (actions land in M3b).
+ * Plan proposals and pending permissions start expanded. Only actual pending
+ * permissions carry the "awaiting approval" banner.
  */
 @Composable
 fun ToolCallBlockView(block: ToolCallBlock, basePath: String?, modifier: Modifier = Modifier) {
@@ -60,7 +60,10 @@ fun ToolCallBlockView(block: ToolCallBlock, basePath: String?, modifier: Modifie
     val resources = LocalContext.current.resources
     val presentation = remember(tool, basePath, resources) { toolCardPresentation(tool, basePath, resources) }
     val pendingPermission = tool.permission?.status == "pending"
-    var expanded by rememberSaveable(block.id) { mutableStateOf(pendingPermission) }
+    val planProposal = isPlanProposalTool(tool.name)
+    // An output-first placeholder can acquire its real tool name later. Open a
+    // newly recognized plan, but retain explicit folding across input updates.
+    var expanded by rememberSaveable(block.id, planProposal) { mutableStateOf(pendingPermission || planProposal) }
     val colors = MaterialTheme.hapi
 
     Surface(
@@ -99,6 +102,14 @@ fun ToolCallBlockView(block: ToolCallBlock, basePath: String?, modifier: Modifie
                 ToolStatusIndicator(tool.state)
             }
 
+            if (planProposal && expanded) {
+                ToolCallBody(
+                    tool = tool,
+                    basePath = basePath,
+                    modifier = Modifier.padding(start = 10.dp, end = 10.dp, bottom = 10.dp),
+                )
+            }
+
             tool.permission?.let { permission ->
                 val interactions = LocalChatInteractions.current
                 if (permission.status == "pending" && interactions != null) {
@@ -126,7 +137,7 @@ fun ToolCallBlockView(block: ToolCallBlock, basePath: String?, modifier: Modifie
                 }
             }
 
-            if (expanded) {
+            if (!planProposal && expanded) {
                 ToolCallBody(
                     tool = tool,
                     basePath = basePath,

android/app/src/main/kotlin/app/hapi/companion/feature/chat/blocks/ToolContentPresentation.kt

@@ -22,6 +22,20 @@ internal fun toolSourceInput(input: JsonElement?, keys: List<String>): String? =
 
 private fun JsonElement?.textValue(): String? = (this as? JsonPrimitive)?.takeIf { it.isString }?.content
 
+internal fun isPlanProposalTool(name: String): Boolean = name == "ExitPlanMode" || name == "exit_plan_mode"
+
+/** A proposal is input.plan Markdown, not update_plan's checklist or a result. */
+internal fun planProposalMarkdown(tool: ChatToolCall): String? =
+    if (isPlanProposalTool(tool.name)) (tool.input as? JsonObject)?.get("plan").textValue()?.takeIf { it.isNotBlank() }
+    else null
+
+internal fun planProposalShowsResult(tool: ChatToolCall): Boolean {
+    if (tool.state == "error") return true
+    val result = tool.result ?: return false
+    if (result is JsonNull) return false
+    return result.textValue()?.isNotBlank() ?: true
+}
+
 /** Mixed content stays JSON, rather than silently discarding images/resources. */
 internal fun extractResultText(result: JsonElement, depth: Int = 0): String? {
     if (depth > 4) return null