Report or block from a story

Android half of ios#56, spec §6.25. Needs the relay endpoint from
flamenet-relay!24.

🔴 A report is the one thing this app sends that the server can read.
Everything else is sealed, and the relay cannot open a story, so a report
about one is only actionable if the reporter hands over what they saw.
The dialog states that before anything is sent: what leaves the device,
who can read it, and that it cannot be undone. Declining to include a
copy is offered, and says plainly there may then be nothing to act on.

⚠️ `reportStory` sends only what it is passed. It does not reach into the
thread for surrounding context — §6.25 forbids including anything the
reporter did not choose to include.

⚠️ Blocking and reporting sit side by side and are never merged. Blocking
is this person's own decision and takes effect now; a report is a request
to somebody else. The copy says which is which, because a combined
control would make one of the two invisible.

The reasons are enumerated to match the relay, and a test asserts the two
lists are equal — a reason the relay rejects is a report somebody
believed they had filed. CSAM is its own reason rather than folded into
abuse: it carries a different obligation, and an operator cannot triage
what nobody can name.

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

client/src/main/kotlin/io/flamenet/client/RelayClient.kt

@@ -339,6 +339,33 @@ class RelayClient(
      * inside the ratchet; putting it anywhere the relay can read defeats the
      * point of encrypting the blob.
      */
+    /**
+     * `POST /e2e/moderation/report` — file a report (§6.25).
+     *
+     * 🔴 **The one call that deliberately sends readable content to the
+     * server.** Everything else this client sends is sealed. A relay that
+     * cannot open a reported story cannot act on an accusation about it, so
+     * the reporter's own copy travels with the report — and the caller is
+     * required to have obtained consent naming that, before reaching here.
+     */
+    fun submitReport(
+        about: Long,
+        kind: String,
+        reason: String,
+        content: String,
+        note: String,
+    ) {
+        val body = JSONObject()
+            .put("about", about)
+            .put("kind", kind)
+            .put("reason", reason)
+            .put("content", content)
+            .put("note", note)
+            .toString()
+        request("POST", url("/e2e/moderation/report"), "/e2e/moderation/report",
+                body.toRequestBody(JSON)).use { it.close() }
+    }
+
     fun uploadAttachment(blob: ByteArray): String =
         request("POST", url("/e2e/attachments"), "/e2e/attachments", blob.toRequestBody(OCTETS))
             .use { json(it).getString("id") }