Feat/rerank model (#2137)

* feat(provider): add rerank model management as a core model type

* feat(provider): add rerank support to existing requesters and new rerank providers

* feat(web): add rerank model management UI and pipeline config

* fix(provider): correct rerank support_type after verification

- Add rerank to OpenRouter (confirmed /api/v1/rerank endpoint)
- Remove rerank from Ollama (no native support, PR #7219 unmerged)
- Remove rerank from JiekouAI (no rerank docs found, URL path mismatch)

* fix(provider): remove alru_cache from model getters and add rerank param hints

* fix: resolve lint errors

- Remove unused alru_cache import from modelmgr.py
- Remove unused error_message variable in invoke_rerank
- Fix prettier formatting in frontend files

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* fix: remove unused exception variable

- Change `except Exception as e:` to `except Exception:` since e is not used
- Fix prettier formatting in ProviderCard.tsx

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* fix: apply ruff format

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* feat(template): add rerank config fields to default pipeline config

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* chore: remove PR.md

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* fix(ui): remove duplicate rerank model form in AddModelPopover

The form was being rendered twice: once in TabsContent manual mode
and again in a separate conditional block for rerank tab.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

src/langbot/templates/default-pipeline-config.json

@@ -52,7 +52,9 @@
                     "content": "You are a helpful assistant."
                 }
             ],
-            "knowledge-bases": []
+            "knowledge-bases": [],
+            "rerank-model": "",
+            "rerank-top-k": 5
         },
         "dify-service-api": {
             "base-url": "https://api.dify.ai/v1",

src/langbot/templates/metadata/pipeline/ai.yaml

@@ -104,6 +104,34 @@ stages:
           field: __system.is_wizard
           operator: neq
           value: true
+      - name: rerank-model
+        label:
+          en_US: Rerank Model
+          zh_Hans: 重排序模型
+        description:
+          en_US: Optional rerank model to improve retrieval quality by re-scoring retrieved chunks
+          zh_Hans: 可选的重排序模型，通过重新评分检索结果来提升检索质量
+        type: rerank-model-selector
+        required: false
+        default: ''
+        show_if:
+          field: knowledge-bases
+          operator: neq
+          value: []
+      - name: rerank-top-k
+        label:
+          en_US: Rerank Top K
+          zh_Hans: 重排序保留数量
+        description:
+          en_US: Number of top results to keep after reranking
+          zh_Hans: 重排序后保留的最相关结果数量
+        type: integer
+        required: false
+        default: 5
+        show_if:
+          field: rerank-model
+          operator: neq
+          value: ''
   - name: dify-service-api
     label:
       en_US: Dify Service API