feat(notifications): per-chat mute settings

- add chat_notification_settings table and migration
- add chat notifications API (get/update muted)
- skip message notifications for muted recipients
- add mute/unmute control in chat info panel

alembic/versions/0009_chat_notification_settings.py

@@ -0,0 +1,52 @@
+"""add chat notification settings
+
+Revision ID: 0009_chat_notification_settings
+Revises: 0008_user_last_seen_presence
+Create Date: 2026-03-08 14:00:00.000000
+"""
+
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+revision: str = "0009_chat_notification_settings"
+down_revision: Union[str, Sequence[str], None] = "0008_user_last_seen_presence"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "chat_notification_settings",
+        sa.Column("id", sa.Integer(), nullable=False),
+        sa.Column("chat_id", sa.Integer(), nullable=False),
+        sa.Column("user_id", sa.Integer(), nullable=False),
+        sa.Column("muted", sa.Boolean(), nullable=False, server_default=sa.text("false")),
+        sa.Column("updated_at", sa.DateTime(timezone=True), nullable=False, server_default=sa.func.now()),
+        sa.ForeignKeyConstraint(["chat_id"], ["chats.id"], name=op.f("fk_chat_notification_settings_chat_id_chats"), ondelete="CASCADE"),
+        sa.ForeignKeyConstraint(["user_id"], ["users.id"], name=op.f("fk_chat_notification_settings_user_id_users"), ondelete="CASCADE"),
+        sa.PrimaryKeyConstraint("id", name=op.f("pk_chat_notification_settings")),
+        sa.UniqueConstraint("chat_id", "user_id", name="uq_chat_notification_settings_chat_user"),
+    )
+    op.create_index(op.f("ix_chat_notification_settings_id"), "chat_notification_settings", ["id"], unique=False)
+    op.create_index(
+        op.f("ix_chat_notification_settings_chat_id"),
+        "chat_notification_settings",
+        ["chat_id"],
+        unique=False,
+    )
+    op.create_index(
+        op.f("ix_chat_notification_settings_user_id"),
+        "chat_notification_settings",
+        ["user_id"],
+        unique=False,
+    )
+
+
+def downgrade() -> None:
+    op.drop_index(op.f("ix_chat_notification_settings_user_id"), table_name="chat_notification_settings")
+    op.drop_index(op.f("ix_chat_notification_settings_chat_id"), table_name="chat_notification_settings")
+    op.drop_index(op.f("ix_chat_notification_settings_id"), table_name="chat_notification_settings")
+    op.drop_table("chat_notification_settings")