## Bug Description

Custom redaction tags (`keyword_redaction_tag` and `pattern_redaction_format`) configuration parameters are not working as documented in v1.87.1.

According to the [official documentation](https://docs.litellm.ai/docs/proxy/guardrails/litellm_content_filter#customizing-tags), these parameters should allow customizing the placeholder format for redacted content.

## Expected Behavior

When configured with: ```yaml keyword_redaction_tag: "***REDACTED***" pattern_redaction_format: "***{pattern_name}***" ```

Redacted content should use the custom placeholders.

## Actual Behavior

Configuration can be saved to database, but **runtime does not read these values**. Placeholders are fixed to default values: - Keywords → `[KEYWORD_REDACTED]` - Patterns → `[{pattern_name}_REDACTED]`

## Test Evidence

### Test 1: Custom keyword_redaction_tag ```bash curl -X POST "http://10.200.9.249:30090/guardrails" \ -H "Authorization: Bearer sk-1234" -H "Content-Type: application/json" \ -d '{ "guardrail": { "guardrail_name": "custom-tag-test", "litellm_params": { "guardrail": "litellm_content_filter", "mode": "pre_call", "default_on": true…