feat(message): add comprehensive message system with database migrations and health checks

- Add database migrations for message base table with indexes for efficient querying
- Implement rich content support with attachment, embed, and poll tables
- Create social features including reactions, bookmarks, mentions, and read states
- Add thread management with participant tracking and resolution capabilities
- Include article posts with title, cover image, tags, and engagement metrics
- Support scheduled messages, stickers, forwards, and interactive components
- Fix UUID defaults and ensure proper uniqueness constraints for drafts
- Add gRPC health server for imks and health check client for appks connectivity
- Replace non-connectable 0.0.0.0 addresses with localhost in service discovery
- Normalize addresses during RPC configuration to handle bind address issues

migrate/001_message_thread_base.sql

@@ -0,0 +1,23 @@
+-- Create message_thread before migrations that reference it.
+-- Safe for existing databases because the table may already exist from 004.
+
+BEGIN;
+
+CREATE TABLE IF NOT EXISTS message_thread (
+    id                     UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    channel_id             UUID NOT NULL,
+    root_message_id        UUID NOT NULL REFERENCES message(id) ON DELETE CASCADE,
+    created_by             UUID NOT NULL,
+    replies_count          BIGINT NOT NULL DEFAULT 0,
+    participants_count     BIGINT NOT NULL DEFAULT 0,
+    last_reply_message_id  UUID NULL REFERENCES message(id) ON DELETE SET NULL,
+    last_reply_at          TIMESTAMPTZ NULL,
+    resolved               BOOLEAN NOT NULL DEFAULT FALSE,
+    resolved_by            UUID NULL,
+    resolved_at            TIMESTAMPTZ NULL,
+    created_at             TIMESTAMPTZ NOT NULL DEFAULT now(),
+    updated_at             TIMESTAMPTZ NOT NULL DEFAULT now(),
+    CONSTRAINT uq_message_thread_root UNIQUE (root_message_id)
+);
+
+COMMIT;