feat: add runtime management database schema (environments, apps, versions, deployments)

- environments, apps, app_versions, deployments tables
- Default environment seeded on migration
- Foreign keys with CASCADE delete

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cameleer3-server-app/src/main/resources/db/migration/V3__runtime_management.sql

@@ -0,0 +1,54 @@
+-- V3__runtime_management.sql
+-- Runtime management: environments, apps, app versions, deployments
+
+CREATE TABLE environments (
+    id              UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    slug            VARCHAR(100) NOT NULL UNIQUE,
+    display_name    VARCHAR(255) NOT NULL,
+    status          VARCHAR(20) NOT NULL DEFAULT 'ACTIVE',
+    created_at      TIMESTAMPTZ NOT NULL DEFAULT now(),
+    updated_at      TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE TABLE apps (
+    id              UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    environment_id  UUID NOT NULL REFERENCES environments(id) ON DELETE CASCADE,
+    slug            VARCHAR(100) NOT NULL,
+    display_name    VARCHAR(255) NOT NULL,
+    created_at      TIMESTAMPTZ NOT NULL DEFAULT now(),
+    updated_at      TIMESTAMPTZ NOT NULL DEFAULT now(),
+    UNIQUE(environment_id, slug)
+);
+CREATE INDEX idx_apps_environment_id ON apps(environment_id);
+
+CREATE TABLE app_versions (
+    id              UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    app_id          UUID NOT NULL REFERENCES apps(id) ON DELETE CASCADE,
+    version         INTEGER NOT NULL,
+    jar_path        VARCHAR(500) NOT NULL,
+    jar_checksum    VARCHAR(64) NOT NULL,
+    jar_filename    VARCHAR(255),
+    jar_size_bytes  BIGINT,
+    uploaded_at     TIMESTAMPTZ NOT NULL DEFAULT now(),
+    UNIQUE(app_id, version)
+);
+CREATE INDEX idx_app_versions_app_id ON app_versions(app_id);
+
+CREATE TABLE deployments (
+    id                  UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    app_id              UUID NOT NULL REFERENCES apps(id) ON DELETE CASCADE,
+    app_version_id      UUID NOT NULL REFERENCES app_versions(id),
+    environment_id      UUID NOT NULL REFERENCES environments(id),
+    status              VARCHAR(20) NOT NULL DEFAULT 'STARTING',
+    container_id        VARCHAR(100),
+    container_name      VARCHAR(255),
+    error_message       TEXT,
+    deployed_at         TIMESTAMPTZ,
+    stopped_at          TIMESTAMPTZ,
+    created_at          TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+CREATE INDEX idx_deployments_app_id ON deployments(app_id);
+CREATE INDEX idx_deployments_env_id ON deployments(environment_id);
+
+-- Default environment (standalone mode always has at least one)
+INSERT INTO environments (slug, display_name) VALUES ('default', 'Default');