feat : add an Encrypted Message Storage (#372)

* feat : add an Encrypted Message Storage

* fix: resolve merge conflict

* fix: resolve merge conflict

* fix: resolve merge conflict

* fix: resolve merge conflict

* fix: resolve merge conflict

* fix: resolve merge conflict

Author: SYLVIANNORUKA

backend/fix_migrations.bat

@@ -0,0 +1,24 @@
+@echo off
+REM Fix all migrations to include uuid-ossp extension
+
+echo Fixing migrations to include uuid-ossp extension...
+
+REM List of migrations that need the fix (excluding init)
+set migrations=20260221151200_add_notifications_and_action_logs.sql 20260224153500_add_nonces.sql 20260226000000_add_lending_events.sql 20260226140000_create_user_2fa.sql 20260324120000_add_emergency_access_tracking.sql 20260324170000_add_emergency_contacts.sql 20260324173000_add_emergency_access_audit_logs.sql 20260324180000_add_emergency_access_risk_alerts.sql 20260325100000_add_pools_for_stress_testing.sql 20260325103000_add_governance_tables.sql 20260325190000_add_emergency_access_sessions.sql
+
+for %%f in (%migrations%) do (
+    echo Checking migrations\%%f
+    findstr /C:"CREATE EXTENSION IF NOT EXISTS \"uuid-ossp\"" migrations\%%f >nul
+    if errorlevel 1 (
+        echo Adding extension to %%f
+        echo -- Ensure UUID extension is available> temp.sql
+        echo CREATE EXTENSION IF NOT EXISTS "uuid-ossp";>> temp.sql
+        echo.>> temp.sql
+        type migrations\%%f >> temp.sql
+        move /Y temp.sql migrations\%%f >nul
+    ) else (
+        echo %%f already has extension
+    )
+)
+
+echo Done!

backend/migrations/20260221120000_add_plans_and_logs.sql

@@ -1,20 +1,15 @@
--- Migration: Add plans and plan_logs tables
-
-CREATE TABLE plans (
-    id SERIAL PRIMARY KEY,
-    user_id INTEGER NOT NULL,
-    amount NUMERIC(20, 6) NOT NULL,
-    fee NUMERIC(20, 6) NOT NULL,
-    net_amount NUMERIC(20, 6) NOT NULL,
-    status VARCHAR(32) NOT NULL,
-    created_at TIMESTAMP NOT NULL DEFAULT NOW(),
-    updated_at TIMESTAMP NOT NULL DEFAULT NOW()
-);
+-- Migration: Add plan_logs table
+-- NOTE:
+-- The plans table is already created in the initial migration.
+-- This migration should only add the dependent plan_logs table.
 
 CREATE TABLE plan_logs (
     id SERIAL PRIMARY KEY,
-    plan_id INTEGER NOT NULL REFERENCES plans(id),
+    plan_id UUID NOT NULL REFERENCES plans(id) ON DELETE CASCADE,
     action VARCHAR(64) NOT NULL,
-    performed_by INTEGER NOT NULL,
-    timestamp TIMESTAMP NOT NULL DEFAULT NOW()
+    performed_by UUID NOT NULL,
+    timestamp TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW()
 );
+
+CREATE INDEX idx_plan_logs_plan_id ON plan_logs(plan_id);
+CREATE INDEX idx_plan_logs_performed_by ON plan_logs(performed_by);

backend/migrations/20260223000000_add_claim_plan_unique_constraint.sql

@@ -1,12 +1,12 @@
 -- Add unique constraint on plan_id in claims table to prevent duplicate claims
 -- This ensures only one claim per plan, preventing race condition vulnerabilities
 
--- First, remove any existing duplicate claims (keep the first one)
+-- First, remove any existing duplicate claims (keep the first one by created_at)
 DELETE FROM claims
 WHERE id NOT IN (
-    SELECT MIN(id)
+    SELECT DISTINCT ON (plan_id) id
     FROM claims
-    GROUP BY plan_id
+    ORDER BY plan_id, created_at ASC
 );
 
 -- Drop the existing unique constraint on (plan_id, beneficiary_email)