feat(tasks): markdown export projection

A disposable Markdown view of the board, grouped by status with checkboxes
and claimants — rendered from the event log, never a source of truth.
TaskMarkdown.render (pure) backs GET /tasks/export[?project=].

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

apps/server/src/main/kotlin/com/correx/apps/server/routes/TaskRoutes.kt

@@ -11,14 +11,17 @@ import com.correx.core.events.types.TaskNoteAuthor
 import com.correx.core.events.types.TaskTargetKind
 import com.correx.core.tasks.Task
 import com.correx.core.tasks.TaskContextAssembler
+import com.correx.core.tasks.TaskMarkdown
 import com.correx.core.tasks.TaskSearch
 import com.correx.core.tasks.TaskService
 import com.correx.core.tasks.TaskStatus
 import com.correx.core.tasks.TaskTargetKinds
 import com.correx.core.utils.TypeId
+import io.ktor.http.ContentType
 import io.ktor.http.HttpStatusCode
 import io.ktor.server.request.receive
 import io.ktor.server.response.respond
+import io.ktor.server.response.respondText
 import io.ktor.server.routing.Route
 import io.ktor.server.routing.RoutingContext
 import io.ktor.server.routing.delete
@@ -150,6 +153,12 @@ private fun Route.taskCollectionRoutes(service: TaskService) {
         )
         call.respond(HttpStatusCode.Created, task.toResponse())
     }
+    // Disposable Markdown projection of the board (whole board, or one project with ?project=).
+    get("/export") {
+        val project = call.request.queryParameters["project"]
+        val tasks = if (project != null) service.list(ProjectId(project)) else service.listAll()
+        call.respondText(TaskMarkdown.render(tasks), ContentType.Text.Plain)
+    }
 }
 
 // Git-driven status: a commit mention advances a task to IN_PROGRESS, a closing keyword

apps/server/src/test/kotlin/com/correx/apps/server/routes/TaskRoutesTest.kt

@@ -227,6 +227,21 @@ class TaskRoutesTest {
         }
     }
 
+    @Test
+    fun `GET tasks export renders the board as markdown`(@TempDir tempDir: Path) {
+        testApplication {
+            application { configureServer(buildModule(tempDir)) }
+            val client = createClient {}
+            client.createTask() // demo-1
+
+            val res = client.get("/tasks/export")
+            assertEquals(HttpStatusCode.OK, res.status)
+            val md = res.bodyAsText()
+            assertTrue(md.startsWith("# Tasks"))
+            assertTrue(md.contains("**demo-1**"))
+        }
+    }
+
     @Test
     fun `context bundle is served for a known task`(@TempDir tempDir: Path) {
         testApplication {