[Apps] Adding support app alpha and dogfooding (#1368)

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<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

* **New Features**
* Support app: inbox UI to create, view, reply, and manage conversations
(status, priority, assignee, tags, internal notes).
* Dashboard pages: Conversations and Support Settings; feedback can
create managed conversations.
* Public/internal APIs for listing, creating, updating, and fetching
conversation details; client-side helpers.

* **SLA**
* Configurable first/next response targets, urgency classification, and
timing logic.

* **Data**
* New conversation persistence (conversations, entry points, messages)
and migration tests; preserves conversations on user/team deletion and
anonymizes sender data.

* **Tests**
  * Unit, migration, and end-to-end tests added.

* **Documentation**
  * Updated docs describing conversation model and workflow rules.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: madster456

apps/backend/prisma/migrations/20260420000000_add_conversations/migration.sql

@@ -0,0 +1,80 @@
+CREATE TABLE "Conversation" (
+    "id" UUID NOT NULL,
+    "tenancyId" UUID NOT NULL,
+    "projectUserId" UUID,
+    "teamId" UUID,
+    "subject" TEXT NOT NULL,
+    "status" TEXT NOT NULL,
+    "priority" TEXT NOT NULL,
+    "source" TEXT NOT NULL,
+    "assignedToUserId" TEXT,
+    "assignedToDisplayName" TEXT,
+    "tags" JSONB,
+    "firstResponseDueAt" TIMESTAMP(3),
+    "firstResponseAt" TIMESTAMP(3),
+    "nextResponseDueAt" TIMESTAMP(3),
+    "lastCustomerReplyAt" TIMESTAMP(3),
+    "lastAgentReplyAt" TIMESTAMP(3),
+    "metadata" JSONB,
+    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMP(3) NOT NULL,
+    "lastMessageAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "lastInboundAt" TIMESTAMP(3),
+    "lastOutboundAt" TIMESTAMP(3),
+    "closedAt" TIMESTAMP(3),
+
+    CONSTRAINT "Conversation_pkey" PRIMARY KEY ("tenancyId","id"),
+    CONSTRAINT "Conversation_status_check" CHECK ("status" IN ('open', 'pending', 'closed')),
+    CONSTRAINT "Conversation_priority_check" CHECK ("priority" IN ('low', 'normal', 'high', 'urgent')),
+    CONSTRAINT "Conversation_source_check" CHECK ("source" IN ('manual', 'chat', 'email', 'api')),
+    CONSTRAINT "Conversation_tenancyId_fkey" FOREIGN KEY ("tenancyId") REFERENCES "Tenancy"("id") ON DELETE CASCADE ON UPDATE CASCADE
+);
+
+CREATE TABLE "ConversationEntryPoint" (
+    "id" UUID NOT NULL,
+    "tenancyId" UUID NOT NULL,
+    "conversationId" UUID NOT NULL,
+    "channelType" TEXT NOT NULL,
+    "adapterKey" TEXT NOT NULL,
+    "externalChannelId" TEXT,
+    "isEntryPoint" BOOLEAN NOT NULL DEFAULT FALSE,
+    "metadata" JSONB,
+    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMP(3) NOT NULL,
+
+    CONSTRAINT "ConversationEntryPoint_pkey" PRIMARY KEY ("tenancyId","id"),
+    CONSTRAINT "ConversationEntryPoint_type_check" CHECK ("channelType" IN ('manual', 'chat', 'email', 'api')),
+    CONSTRAINT "ConversationEntryPoint_tenancyId_fkey" FOREIGN KEY ("tenancyId") REFERENCES "Tenancy"("id") ON DELETE CASCADE ON UPDATE CASCADE,
+    CONSTRAINT "ConversationEntryPoint_tenancyId_conversationId_fkey" FOREIGN KEY ("tenancyId", "conversationId") REFERENCES "Conversation"("tenancyId", "id") ON DELETE CASCADE ON UPDATE CASCADE
+);
+
+CREATE TABLE "ConversationMessage" (
+    "id" UUID NOT NULL,
+    "tenancyId" UUID NOT NULL,
+    "conversationId" UUID NOT NULL,
+    "channelId" UUID,
+    "messageType" TEXT NOT NULL,
+    "senderType" TEXT NOT NULL,
+    "senderId" TEXT,
+    "senderDisplayName" TEXT,
+    "senderPrimaryEmail" TEXT,
+    "body" TEXT,
+    "attachments" JSONB,
+    "metadata" JSONB,
+    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "ConversationMessage_pkey" PRIMARY KEY ("tenancyId","id"),
+    CONSTRAINT "ConversationMessage_messageType_check" CHECK ("messageType" IN ('message', 'internal-note', 'status-change')),
+    CONSTRAINT "ConversationMessage_senderType_check" CHECK ("senderType" IN ('user', 'agent', 'system')),
+    CONSTRAINT "ConversationMessage_tenancyId_fkey" FOREIGN KEY ("tenancyId") REFERENCES "Tenancy"("id") ON DELETE CASCADE ON UPDATE CASCADE,
+    CONSTRAINT "ConversationMessage_tenancyId_conversationId_fkey" FOREIGN KEY ("tenancyId", "conversationId") REFERENCES "Conversation"("tenancyId", "id") ON DELETE CASCADE ON UPDATE CASCADE,
+    CONSTRAINT "ConversationMessage_tenancyId_channelId_fkey" FOREIGN KEY ("tenancyId", "channelId") REFERENCES "ConversationEntryPoint"("tenancyId", "id") ON DELETE NO ACTION ON UPDATE CASCADE
+);
+
+CREATE INDEX "Conversation_user_lastMessageAt_idx" ON "Conversation"("tenancyId", "projectUserId", "lastMessageAt" DESC);
+CREATE INDEX "Conversation_status_lastMessageAt_idx" ON "Conversation"("tenancyId", "status", "lastMessageAt" DESC);
+CREATE INDEX "Conversation_team_lastMessageAt_idx" ON "Conversation"("tenancyId", "teamId", "lastMessageAt" DESC);
+CREATE INDEX "ConversationEntryPoint_conversation_createdAt_idx" ON "ConversationEntryPoint"("tenancyId", "conversationId", "createdAt");
+CREATE INDEX "ConversationEntryPoint_type_adapter_idx" ON "ConversationEntryPoint"("tenancyId", "channelType", "adapterKey");
+CREATE INDEX "ConversationMessage_conversation_createdAt_idx" ON "ConversationMessage"("tenancyId", "conversationId", "createdAt");
+CREATE INDEX "ConversationMessage_channel_createdAt_idx" ON "ConversationMessage"("tenancyId", "channelId", "createdAt");