feat: initial commit

Axum/Postgres server with auth, migrations, and Docker setup.

migrations/20260812140000_create_messages.up.sql

@@ -0,0 +1,31 @@
+CREATE TABLE messages (
+    id              UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    conversation_id UUID        NOT NULL REFERENCES conversations(id) ON DELETE CASCADE,
+    user_id         UUID        NOT NULL REFERENCES users(id),
+    content         TEXT        NOT NULL,
+    created_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    updated_at      TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    deleted_at      TIMESTAMPTZ
+);
+
+CREATE TABLE attachments (
+    id         UUID   PRIMARY KEY DEFAULT gen_random_uuid(),
+    message_id UUID   NOT NULL REFERENCES messages(id) ON DELETE CASCADE,
+    url        TEXT   NOT NULL,
+    filename   TEXT   NOT NULL,
+    mime_type  TEXT   NOT NULL,
+    size_bytes BIGINT NOT NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+CREATE TABLE reactions (
+    id         UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    message_id UUID NOT NULL REFERENCES messages(id) ON DELETE CASCADE,
+    user_id    UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    emoji      TEXT NOT NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    UNIQUE (message_id, user_id, emoji)
+);
+
+CREATE INDEX messages_conversation_id_created_at_idx ON messages(conversation_id, created_at DESC);
+CREATE INDEX reactions_message_id_idx                ON reactions(message_id);