Please address the comments from this code review:

## Overall Comments
- In `_grants_get_schema_object_privs`, the `_role` variable is constructed but never used; consider removing it or using it to make the intent clearer and avoid confusion.
- The `grant_schema_object_privileges` macro’s revoke_query filters only on `object_schema` and `privilege_type` but not on `object_type`, which may cause revokes on unintended object types; consider narrowing the query to the specific `object_type` being processed.
- The `schemas_skipped` tracking in `grant_schema_read_specific` uses a list with a dummy initial element and `length - 1` arithmetic; replacing this with a simple integer counter would make the skip-count logic easier to read and maintain.

## Individual Comments

### Comment 1
<location path="macros/grants/grant_schema_read.sql" line_range="61-70" />
<code_context>
+    {% set existing_privs = dbt_dataengineers_utils._grants_get_schema_object_privs(schema, ['SELECT', 'REFERENCES', 'REBUILD', 'READ'], grant_roles) %}
</code_context>
<issue_to_address>
**issue (bug_risk):** Existing object privileges are checked per-role only, which may skip granting SELECT on some object types.

`_grants_get_schema_object_privs` aggregates privileges per grantee without distinguishing object types or whether they apply to all objects. This code treats any existing `SELECT` for a role as meaning no further `SELECT` grants are needed, and then skips granting on views, materialized views, tables, external tables, dynamic tables, and streams.

As a result, roles that currently have `SELECT` on only some objects may never receive `SELECT` on the remaining ones, changing behavior from the previous `grant ... on all ...` pattern. If you want to maintain full read coverage while keeping the operation idempotent, consider tracking existing privileges per object type or reverting to unconditional `grant ... on all ...` and relying on Snowflake’s idempotence.
</issue_to_address>

### Comment 2
<location path="macros/grants/grant_schema_object_privileges.sql" line_range="58-67" />
<code_context>
+    {% set existing_privs = dbt_dataengineers_utils._grants_get_schema_object_privs(schema_name, permission_list, role_list) %}
</code_context>
<issue_to_address>
**issue (bug_risk):** The bulk helper ignores `object_type`, so revokes/grants may consider privileges on unrelated objects in the schema.

In `grant_schema_object_privileges`, the bulk path calls `_grants_get_schema_object_privs(schema_name, permission_list, role_list)` and builds a revoke query on `information_schema.object_privileges` filtered only by `object_schema` and `privilege_type`, ignoring the `object_type` argument.

As a result:
- A call with `object_type='TABLE'` may treat privileges on views, streams, etc. as if they applied to tables when deciding which roles already have a privilege.
- The revoke logic may target roles based on privileges they hold on other object types, even though the generated statement is `REVOKE ... ON ALL <object_type>s IN SCHEMA ...`.

To avoid incorrect grant/revoke behavior, the queries should either filter by `object_type` or the bulk helper should be limited to cases where its semantics match the object-type-specific logic.
</issue_to_address>

### Comment 3
<location path="macros/grants/_helpers.sql" line_range="125-134" />
<code_context>
+{% macro _grants_get_schema_object_privs(schema, privilege_types, grantees) %}
</code_context>
<issue_to_address>
**suggestion (bug_risk):** Unused `_role` variable and mixed casing in the grantee filter can be cleaned up for clarity.

Inside `_grants_get_schema_object_privs`:
- `_role = row[0] ~ '::' ~ row[1]` is computed but never used.
- `priv_filter` is uppercased, but `grantees` is not, even though callers currently pass uppercased roles via `_grants_normalize_roles`.

Please remove `_role`, and either normalize `grantees` here or clearly document/enforce the expectation that callers pass uppercased values (e.g. via a `grantees_upper` parameter name) to avoid subtle casing-related bugs.

Suggested implementation:

```
{# Bulk check: returns dict {role: [privs]} for a given schema from information_schema.object_privileges.
   Filters by optional privilege_types list and grantee list. Grantees are normalized to UPPER() to avoid casing issues. #}
{% macro _grants_get_schema_object_privs(schema, privilege_types, grantees) %}
    {% set result_map = {} %}
    {% set priv_filter = privilege_types | map('upper') | list %}
    {% set grantees_upper = grantees | map('upper') | list %}
    {% set query %}
        select privilege_type, grantee
        from information_schema.object_privileges
        where object_schema = '{{ schema }}'
        {% if priv_filter | length > 0 %}
          and privilege_type in ({{ priv_filter | map('tojson') | join(', ') }})
        {% endif %}
        {% if grantees_upper | length > 0 %}

```

1. Remove the unused `_role = row[0] ~ '::' ~ row[1]` assignment inside `_grants_get_schema_object_privs`; the local `_role` variable is not referenced anywhere and should simply be deleted.
2. Anywhere in `_grants_get_schema_object_privs` that currently uses `grantees` to build the SQL (e.g. an `and grantee in (...)` clause) or to filter results in Python/Jinja should be updated to use `grantees_upper` instead:
   - In the SQL, compare against `UPPER(grantee)` or ensure grantees are uppercased consistently with `grantees_upper`.
   - In any subsequent logic that checks membership or builds `result_map`, use `grantees_upper` for comparison to ensure casing-safe behavior.
3. If there is helper documentation or comments elsewhere that mention that callers must pass uppercased grantees (e.g. via `_grants_normalize_roles`), update those comments to reflect that `_grants_get_schema_object_privs` now performs its own uppercasing internally.
</issue_to_address>

### Comment 4
<location path="macros/grants/grant_schema_operate.sql" line_range="21-30" />
<code_context>
+{% macro _grants_get_schema_object_privs(schema, privilege_types, grantees) %}
+    {% set result_map = {} %}
+    {% set priv_filter = privilege_types | map('upper') | list %}
+    {% set query %}
+        select privilege_type, grantee
+        from information_schema.object_privileges
</code_context>
<issue_to_address>
**question (bug_risk):** Revoke statements now use bulk `revoke operate on all tasks/pipes` which may be broader than the previous per-object revokes.

Previously, revokes were per object:
```sql
revoke operate on <object_type> in schema <db>.<object> from role <role>;
```
Now, for non-managed roles, you use bulk revokes:
```sql
revoke operate on all tasks in schema ... from role ...;
revoke operate on all pipes in schema ... from role ...;
```
This changes semantics: a role that had OPERATE on only some tasks/pipes will now lose it on *all* tasks/pipes in the schema, including grants not originally managed by this macro.

Please confirm whether the macro is intended to fully own OPERATE on tasks/pipes for the schema. If not, consider reverting to per-object revokes or scoping bulk revokes to objects discovered by a dedicated query to avoid unintentionally removing other grants.
</issue_to_address>