Consolidate README documentation

Author: amar-python

README.md

@@ -97,8 +97,7 @@ PostgreDataMigrationApp/
 │   ├── variables.tf
 │   ├── outputs.tf
 │   ├── terraform.tfvars.example
-│   ├── .gitignore
-│   └── README.md
+│   └── .gitignore
 │
 ├── setup.sh                        ← Interactive multi-database configuration wizard
 ├── deploy_all.sh                   ← Multi-engine deployment router
@@ -206,6 +205,30 @@ ORDER  BY r.req_identifier;
 
 ---
 
+## CSV Loader
+
+`csv_loader.sh` validates CSV files, derives the target table name from the filename unless `--table` is supplied, writes accepted/skipped row outputs under `csv/logs/`, and routes valid rows to the selected engine-specific loader.
+
+```bash
+# Load into the engine from config.local.env
+./csv_loader.sh data/customers.csv
+
+# Specify engine/environment
+./csv_loader.sh data/orders.csv --engine postgresql --env dev
+
+# Validate only
+./csv_loader.sh data/products.csv --engine sqlite --dry-run
+
+# Override the target table name
+./csv_loader.sh data/export_2025.csv --engine mariadb --table invoices
+```
+
+CSV inputs must have a header row, use comma delimiters, and be UTF-8 encoded with or without a BOM. The shared Python validator skips empty rows and row/header column-count mismatches, warns on duplicate headers, preserves quoted commas/newlines, and writes rejected rows with an `_skip_reason` column.
+
+Supported loader backends are PostgreSQL, MariaDB/MySQL, SQLite, InfluxDB, Redis, and Teradata. PostgreSQL uses `COPY`, MariaDB/MySQL uses `LOAD DATA LOCAL INFILE`, SQLite uses Python `csv` + `sqlite3`, InfluxDB writes line protocol via the `influx` CLI, Redis writes hashes through `redis-cli`, and Teradata uses BTEQ/FastLoad tooling.
+
+---
+
 ## How Parameterisation Works
 
 Every environment file contains **only a `\set` configuration block** followed by `\i te_core_schema.sql`. All logic lives in the core schema — the environment file is pure configuration.

csv/README.md

@@ -9,12 +9,12 @@
 |--------------|-----------|
 | `evals/PLAN.md` | Scope, folder layout, tiering, phases |
 | `evals/FAILURE_MODES.md` | 29 catalogued failure modes; all 22 Tier P modes now covered |
-| `evals/README.md` | How to run; CLI flags; exit codes |
+| root `README.md` + `evals/USAGE.md` | How to run; CLI flags; exit codes |
 | `evals/runner.py` | Single-file scenario discovery + diff engine + JSON report writer (606 lines) |
 | `evals/datasets/tier_p/01-23/` | 23 CSV scenarios (happy + empty + malformed + unicode + generated edge cases) |
-| `evals/datasets/tier_i/01_deploy_dev_twice/` | Idempotency scenario (README only — runner drives the work) |
+| `evals/datasets/tier_i/01_deploy_dev_twice/` | Idempotency scenario (NOTES only; runner drives the work) |
 | `evals/datasets/tier_s/01_fresh_deploy_then_all_tests_pass/` | SQL-suite integration scenario |
-| `evals/expected/tier_p/*.json` | 20 expected-outcome files |
+| `evals/expected/tier_p/*.json` | 23 expected-outcome files |
 | `evals/expected/tier_i/01_deploy_dev_twice.json` | Expected outcome (exit codes + row-count parity) |
 | `evals/expected/tier_s/01_fresh_deploy_then_all_tests_pass.json` | Expected outcome (85/85 + ALL TESTS PASSED) |
 | `evals/reports/` | Auto-created at runtime; one folder per run with `summary.json` |
@@ -38,7 +38,7 @@ cd "$env:USERPROFILE\OneDrive\Desktop\Migration using ai\PostgreDataMigrationApp
 python evals\runner.py
 ```
 
-Expect: `total: 20, passed: 20, failed: 0, skipped: 0` and exit code 0.
+Expect: `total: 23, passed: 23, failed: 0, skipped: 0` and exit code 0.
 
 ### 2. Run Tier I + S against your local PostgreSQL
 
@@ -107,11 +107,11 @@ Catalogued in `FAILURE_MODES.md` so they're not lost.
 
 | Category | Count |
 |----------|-------|
-| Markdown docs (PLAN, FAILURE_MODES, README, HANDOFF) | 4 |
+| Markdown docs (root README, PLAN, FAILURE_MODES, USAGE, HANDOFF) | 5 |
 | Python (`runner.py`) | 1 |
 | CSV input fixtures | 20 (scenarios 19, 20, 22, and 23 are generated/no-input scenarios) |
 | Expected JSON files | 25 |
-| Scenario README/TXT files | 4 |
+| Scenario note/TXT files | 4 |
 | **Total files created** | **55** |
 
 ## Open items

evals/HANDOFF.md

@@ -34,7 +34,6 @@ PostgreDataMigrationApp/
 └── evals/
     ├── PLAN.md                          ← this file
     ├── FAILURE_MODES.md                 ← failure-mode catalogue
-    ├── README.md                        ← how to run it
     ├── runner.py                        ← scenario discovery + diff engine + report
     │
     ├── datasets/
@@ -46,11 +45,11 @@ PostgreDataMigrationApp/
     │   │
     │   ├── tier_i/                      ← idempotency scenarios
     │   │   └── 01_deploy_dev_twice/
-    │   │       └── README.md            ← what the runner does (no CSV needed)
+    │   │       └── NOTES.txt            ← what the runner does (no CSV needed)
     │   │
     │   └── tier_s/                      ← SQL suite integration
     │       └── 01_fresh_deploy_then_all_tests_pass/
-    │           └── README.md
+    │           └── NOTES.txt
     │
     ├── expected/
     │   ├── tier_p/
@@ -112,7 +111,7 @@ Exit code: 0 if all scenarios in selected tiers pass, 1 otherwise. CI-friendly.
 
 | Phase | What | Status |
 |-------|------|--------|
-| 0 | This PLAN + FAILURE_MODES + README | **DONE** |
+| 0 | PLAN + FAILURE_MODES + root README coverage | **DONE** |
 | 1 | Tier P dataset folders (23 scenarios) + expected JSONs | DONE |
 | 2 | Tier P runner.py | DONE |
 | 3 | Execute Tier P locally; show results | DONE / awaiting your review |