fix: Remove deprecated Pangea integration

The Pangea security integration is being deprecated. This PR removes:
- pangea.textGuard check type
- pangea.pii check type
- PangeaTextGuardParameters schema (which had an 'overrides' field causing Go SDK build issues)
- PangeaPIIParameters schema
- Related examples

This also fixes a Go SDK build error where the PangeaTextGuardParameters.Overrides
field conflicted with the param.ParamStruct interface's Overrides() method.

Author: roh26it

openapi.yaml

@@ -2317,28 +2317,6 @@ paths:
                     onFail: "block"
                     message: "Mistral moderation flagged content"
 
-              pangea_security:
-                summary: "[PARTNER] Pangea Security Suite"
-                value:
-                  name: "Pangea Text & PII Guard"
-                  workspace_id: "550e8400-e29b-41d4-a716-446655440000"
-                  checks:
-                    - id: "pangea.textGuard"
-                      parameters:
-                        recipe: "default_text_recipe"
-                        debug: true
-                        overrides:
-                          prompt_guard:
-                            state: "enabled"
-                        timeout: 5000
-                    - id: "pangea.pii"
-                      parameters:
-                        redact: true
-                        timeout: 5000
-                  actions:
-                    onFail: "block"
-                    message: "Pangea security scan failed"
-
               bedrock_enterprise:
                 summary: "[PARTNER] AWS Bedrock Guardrails"
                 value:
@@ -32311,8 +32289,6 @@ components:
             - "patronus.toxicity"
             - "patronus.custom"
             - "mistral.moderateContent"
-            - "pangea.textGuard"
-            - "pangea.pii"
             - "bedrock.guard"
             - "promptfoo.guard"
             - "promptfoo.pii"
@@ -32348,8 +32324,6 @@ components:
             - $ref: '#/components/schemas/PortkeyLanguageParameters'
             - $ref: '#/components/schemas/PortkeyPIIParameters'
             - $ref: '#/components/schemas/MistralModerationParameters'
-            - $ref: '#/components/schemas/PangeaTextGuardParameters'
-            - $ref: '#/components/schemas/PangeaPIIParameters'
             - $ref: '#/components/schemas/BedrockGuardParameters'
             - $ref: '#/components/schemas/PromptfooParameters'
             - $ref: '#/components/schemas/AcuvityScanParameters'
@@ -32974,38 +32948,6 @@ components:
           description: Timeout in milliseconds
           default: 5000
 
-    PangeaTextGuardParameters:
-      type: object
-      required:
-        - recipe
-      properties:
-        recipe:
-          type: string
-          description: Recipe key for Pangea configuration
-        debug:
-          type: boolean
-          description: Enable detailed analysis
-        overrides:
-          type: object
-          additionalProperties: true
-          description: Pangea overrides
-        timeout:
-          type: number
-          description: Timeout in milliseconds
-          default: 5000
-
-    PangeaPIIParameters:
-      type: object
-      properties:
-        redact:
-          type: boolean
-          description: Whether to redact detected PII
-          default: false
-        timeout:
-          type: number
-          description: Timeout in milliseconds
-          default: 5000
-
     BedrockGuardParameters:
       type: object
       required: