chore: PostgreSQL migration compatibility and infrastructure improvements

Database & Migrations:
- Update all Alembic migrations for PostgreSQL compatibility
- Remove SQLite-specific syntax (AUTOINCREMENT, etc.)
- Add database utility helpers for PostgreSQL operations
- Fix services to use PostgreSQL-compatible queries

Documentation:
- Add comprehensive Docker deployment guide
- Add production deployment documentation
- Add infrastructure architecture documentation
- Update database setup guide for PostgreSQL-only
- Expand troubleshooting guide

Architecture & Validation:
- Add migration.yaml rules for SQL compatibility checking
- Enhance validate_architecture.py with migration validation
- Update architecture rules to validate Alembic migrations

Development:
- Fix duplicate install-all target in Makefile
- Add Celery/Redis validation to install.py script
- Add docker-compose.test.yml for CI testing
- Add squash_migrations.py utility script
- Update tests for PostgreSQL compatibility
- Improve test fixtures in conftest.py

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

alembic/versions/r6f7a8b9c0d1_add_country_iso_to_addresses.py

@@ -13,6 +13,7 @@ making changes.
 
 from alembic import op
 import sqlalchemy as sa
+from sqlalchemy import text
 
 
 # revision identifiers, used by Alembic.
@@ -59,9 +60,12 @@ COUNTRY_ISO_MAP = {
 
 
 def get_column_names(connection, table_name):
-    """Get list of column names for a table."""
-    result = connection.execute(sa.text(f"PRAGMA table_info({table_name})"))
-    return [row[1] for row in result]
+    """Get list of column names for a table (PostgreSQL)."""
+    result = connection.execute(text(
+        "SELECT column_name FROM information_schema.columns "
+        "WHERE table_name = :table AND table_schema = 'public'"
+    ), {"table": table_name})
+    return [row[0] for row in result]
 
 
 def upgrade() -> None:
@@ -78,25 +82,25 @@ def upgrade() -> None:
         print("  Columns country_name and country_iso already exist, skipping")
         return
 
-    # If has old 'country' column, rename it and add country_iso
+    # If has old 'country' column, rename it (PostgreSQL supports direct rename)
     if has_country and not has_country_name:
-        with op.batch_alter_table("customer_addresses") as batch_op:
-            batch_op.alter_column(
-                "country",
-                new_column_name="country_name",
-            )
+        op.alter_column(
+            "customer_addresses",
+            "country",
+            new_column_name="country_name",
+        )
 
     # Add country_iso if it doesn't exist
     if not has_country_iso:
-        with op.batch_alter_table("customer_addresses") as batch_op:
-            batch_op.add_column(
-                sa.Column("country_iso", sa.String(5), nullable=True)
-            )
+        op.add_column(
+            "customer_addresses",
+            sa.Column("country_iso", sa.String(5), nullable=True)
+        )
 
         # Backfill country_iso from country_name
         for country_name, iso_code in COUNTRY_ISO_MAP.items():
             connection.execute(
-                sa.text(
+                text(
                     "UPDATE customer_addresses SET country_iso = :iso "
                     "WHERE country_name = :name"
                 ),
@@ -105,19 +109,19 @@ def upgrade() -> None:
 
         # Set default for any remaining NULL values
         connection.execute(
-            sa.text(
+            text(
                 "UPDATE customer_addresses SET country_iso = 'LU' "
                 "WHERE country_iso IS NULL"
             )
         )
 
-        # Make country_iso NOT NULL using batch operation
-        with op.batch_alter_table("customer_addresses") as batch_op:
-            batch_op.alter_column(
-                "country_iso",
-                existing_type=sa.String(5),
-                nullable=False,
-            )
+        # Make country_iso NOT NULL (PostgreSQL supports direct alter)
+        op.alter_column(
+            "customer_addresses",
+            "country_iso",
+            existing_type=sa.String(5),
+            nullable=False,
+        )
 
 
 def downgrade() -> None:
@@ -130,12 +134,11 @@ def downgrade() -> None:
 
     # Only downgrade if in the new state
     if has_country_name and not has_country:
-        with op.batch_alter_table("customer_addresses") as batch_op:
-            batch_op.alter_column(
-                "country_name",
-                new_column_name="country",
-            )
+        op.alter_column(
+            "customer_addresses",
+            "country_name",
+            new_column_name="country",
+        )
 
     if has_country_iso:
-        with op.batch_alter_table("customer_addresses") as batch_op:
-            batch_op.drop_column("country_iso")
+        op.drop_column("customer_addresses", "country_iso")