NOTE: This PR was created with AI tools and a human.

- Remove unused copy command (leftover from deleted agload_test_graph test)
- Replace broken Section 4 that referenced non-existent graph with
  comprehensive WHERE clause tests covering string, int, bool, and float
  properties with AND/OR/NOT operators
- Add EXPLAIN tests to verify index usage:
  - Section 3: Validate GIN indices (load_city_gin_idx, load_country_gin_idx)
    show Bitmap Index Scan for property matching
  - Section 4: Validate all expression indices (city_country_code_idx,
    city_id_idx, city_west_coast_idx, country_life_exp_idx) show Index Scan
    for WHERE clause filtering

All indices now have EXPLAIN verification confirming they are used as expected.

modified:   regress/expected/index.out
modified:   regress/sql/index.sql

NOTE: This PR was created with AI tools and a human.

- Remove unused copy command (leftover from deleted agload_test_graph test)
- Replace broken Section 4 that referenced non-existent graph with
  comprehensive WHERE clause tests covering string, int, bool, and float
  properties with AND/OR/NOT operators
- Add EXPLAIN tests to verify index usage:
  - Section 3: Validate GIN indices (load_city_gin_idx, load_country_gin_idx)
    show Bitmap Index Scan for property matching
  - Section 4: Validate all expression indices (city_country_code_idx,
    city_id_idx, city_west_coast_idx, country_life_exp_idx) show Index Scan
    for WHERE clause filtering

All indices now have EXPLAIN verification confirming they are used as expected.

modified:   regress/expected/index.out
modified:   regress/sql/index.sql

NOTE: This PR was created with AI tools and a human.

- Remove unused copy command (leftover from deleted agload_test_graph test)
- Replace broken Section 4 that referenced non-existent graph with
  comprehensive WHERE clause tests covering string, int, bool, and float
  properties with AND/OR/NOT operators
- Add EXPLAIN tests to verify index usage:
  - Section 3: Validate GIN indices (load_city_gin_idx, load_country_gin_idx)
    show Bitmap Index Scan for property matching
  - Section 4: Validate all expression indices (city_country_code_idx,
    city_id_idx, city_west_coast_idx, country_life_exp_idx) show Index Scan
    for WHERE clause filtering

All indices now have EXPLAIN verification confirming they are used as expected.

modified:   regress/expected/index.out
modified:   regress/sql/index.sql

NOTE: This PR was created with AI tools and a human.

- Remove unused copy command (leftover from deleted agload_test_graph test)
- Replace broken Section 4 that referenced non-existent graph with
  comprehensive WHERE clause tests covering string, int, bool, and float
  properties with AND/OR/NOT operators
- Add EXPLAIN tests to verify index usage:
  - Section 3: Validate GIN indices (load_city_gin_idx, load_country_gin_idx)
    show Bitmap Index Scan for property matching
  - Section 4: Validate all expression indices (city_country_code_idx,
    city_id_idx, city_west_coast_idx, country_life_exp_idx) show Index Scan
    for WHERE clause filtering

All indices now have EXPLAIN verification confirming they are used as expected.

modified:   regress/expected/index.out
modified:   regress/sql/index.sql