feat: Add comprehensive database schema migrations for all platform tables

- Add subscribers table with IMSI, MSISDN, authentication keys, and eSIM profile fields
- Add service_plans table for data/voice/SMS limits and QoS parameters (ARPA, AMBR)
- Add sessions table for tracking PDU sessions with QoS and usage metrics
- Add usage_records table for billing and charging data
- Add users table with role-based access control fields
- Add roles, permissions, and role_permissions junction table for RBAC
- Add auth

migrations/00005_init_sessions.sql

@@ -0,0 +1,37 @@
+-- +goose Up
+-- Create sessions table
+CREATE TABLE IF NOT EXISTS sessions (
+    id           SERIAL PRIMARY KEY,
+    subscriber_id INTEGER NOT NULL,
+    session_id   TEXT NOT NULL UNIQUE,
+    pdu_address  TEXT,
+    dnn          TEXT,
+    snssai_sst   SMALLINT,
+    snssai_sd    INTEGER,
+    qos_qci      SMALLINT,
+    qos_arpa     INTEGER,
+    qos_mbr_uplink   INTEGER,
+    qos_mbr_downlink INTEGER,
+    qos_gbr_uplink   INTEGER,
+    qos_gbr_downlink INTEGER,
+    qos_priority SMALLINT,
+    status       TEXT NOT NULL DEFAULT 'active',
+    start_time   TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    end_time     TIMESTAMPTZ,
+    data_used    BIGINT NOT NULL DEFAULT 0,
+    voice_used   INTEGER NOT NULL DEFAULT 0,
+    sms_used     INTEGER NOT NULL DEFAULT 0,
+    created_at   TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    updated_at   TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    deleted_at   TIMESTAMPTZ
+);
+
+-- Create indexes
+CREATE INDEX IF NOT EXISTS idx_sessions_subscriber_id ON sessions(subscriber_id);
+CREATE INDEX IF NOT EXISTS idx_sessions_session_id ON sessions(session_id);
+CREATE INDEX IF NOT EXISTS idx_sessions_status ON sessions(status);
+CREATE INDEX IF NOT EXISTS idx_sessions_deleted_at ON sessions(deleted_at);
+
+-- +goose Down
+-- Drop sessions table
+DROP TABLE IF EXISTS sessions CASCADE;