Update README to reflect changes in test infrastructure organization and task decomposition workflow. Remove obsolete E2E test templates and clarify input specifications for integration tests. Enhance documentation for planning and implementation phases, including new directory structures and task management processes.

.cursor/rules/sql.mdc

@@ -0,0 +1,15 @@
+---
+description: "SQL and database migration conventions: naming, safety, parameterized queries, indexing, Postgres"
+globs: ["**/*.sql", "**/migrations/**", "**/Migrations/**"]
+---
+# SQL / Migrations
+
+- Use lowercase for SQL keywords (or match project convention); snake_case for table/column names
+- Every migration must be reversible (include DOWN/rollback)
+- Never rename tables or columns without explicit confirmation — prefer additive changes
+- Use parameterized queries; never concatenate user input into SQL
+- Add indexes for columns used in WHERE, JOIN, ORDER BY
+- Use transactions for multi-step data changes
+- Include `NOT NULL` constraints by default; explicitly allow `NULL` only when needed
+- Name constraints explicitly: `pk_table`, `fk_table_column`, `idx_table_column`
+- Test migrations against a copy of production schema before applying