### What problem does this PR solve?

Upgrade MCP SDK to v1.9.4 (latest).

### Type of change

- [x] Refactoring

### What problem does this PR solve?

Update .env ,Defaults to the v0.19.1-slim edition

### Type of change

- [x] Other (please describe): Update .env ,Defaults to the
v0.19.1-slim edition

### What problem does this PR solve?

- Simplify AzureChat constructor by passing base_url directly
- Clean up spacing and formatting in chat_model.py
- Remove redundant parentheses and improve code consistency
- #8423

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

_Briefly describe what this PR aims to solve. Include background context
that will help reviewers understand the purpose of the PR._

### Type of change: Documentation Update/Refactoring

#### Summary
Adds HTTPS/SSL configuration guide/example to enable secure RAGFlow
deployments with proper certificate management.

#### Changes
- New HTTPS Setup Section: Step-by-step guide for SSL certificate
configuration
- Let's Encrypt Integration: Complete Certbot setup instructions
- Docker Configuration: Volume mapping examples for certificates

#### Key Features
- Prerequisites checklist
- Docker Compose configuration examples
- Support for both Let's Encrypt and existing certificates

#### Files Modified
- `README.md`
- `ragflow.https.conf` (new file)

### What problem does this PR solve?

Feat: The delete button is displayed only when the cursor is hovered
over the connection line #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

**Context and Purpose:**

This PR automatically remediates a security vulnerability:
- **Description:** Detected possible formatted SQL query. Use
parameterized queries instead.
- **Rule ID:**
python.lang.security.audit.formatted-sql-query.formatted-sql-query
- **Severity:** HIGH
- **File:** rag/utils/opendal_conn.py
- **Lines Affected:** 98 - 98

This change is necessary to protect the application from potential
security risks associated with this vulnerability.

**Solution Implemented:**

The automated remediation process has applied the necessary changes to
the affected code in `rag/utils/opendal_conn.py` to resolve the
identified issue.

Please review the changes to ensure they are correct and integrate as
expected.

### What problem does this PR solve?

#8406

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

Feat: Solved the conflict between the Handle click and drag events of
the canvas node #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

#8414

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?
#8391
#8404

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

---------

Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>

### What problem does this PR solve?

### Type of change

- [x] Documentation Update

### What problem does this PR solve?

Feat: Add Tavily operator #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Fix: Fixed the issue where tag content would overflow the container
#8392
### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

Refactor Pdf 2 Slices page to new style

### Type of change

- [X] Refactoring

### What problem does this PR solve?

Feat: Improve the tavily form #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Fix code debug may corrupt by history answer.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

https://github.com/infiniflow/ragflow/issues/8360

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

Add curl example for interacting with the RAGFlow MCP server. Special
thanks to @writinwaters for his expert refinement.

### Type of change

- [x] Documentation Update

---------

Co-authored-by: writinwaters <cai.keith@gmail.com>

### What problem does this PR solve?

Feat: Synchronize the data of the tavily form to the canvas node #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Feat: Deleting the last tool of the agent will delete the tool node
#3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Refactor Datasets UI #3221.
### Type of change

- [X] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Feat: Save the agent tool data to the node #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

- Update Docker image version badges and references from v0.19.0 to
v0.19.1
- Modify version mentions in all localized README files (id, ja, ko,
pt_br, tzh, zh)
- Update version in docker/README.md and related documentation files
- Includes updates to Helm values and Python SDK dependencies

### Type of change

- [x] Documentation Update

### What problem does this PR solve?

- Correct boolean parsing for 'desc' parameter in document_app.py to
properly handle string values

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

The existing
/api/v1/datasets/{dataset_id}/documents/{document_id}/chunks endpoint
fails to accurately return a document's chunk status. Even when a chunk
is explicitly marked as unavailable, the API still returns true.

![img_v3_02nc_3458a1b7-609e-4f20-8cb7-2156a489848g](https://github.com/user-attachments/assets/ab3b8f69-1284-49c1-8af3-bdfae3416583)

![img_v3_02nc_82f1d96e-7596-4def-ba75-5a2bd10d56cg](https://github.com/user-attachments/assets/a8a4162b-b50d-4dfc-af72-e1d7812a0a93)

Co-authored-by: zhoudeyong <zhoudeyong@idr.ai>

### What problem does this PR solve?


### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

Fixes a minor grammar issue in a user-facing error message. The original
message said "large than" instead of the correct comparative form
"larger than". Just a quick fix I noticed while reading the code.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

Fix: Fixed the issue where the initial value of the slice method was not
displayed in the dialog box #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Wrap search app

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?


### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

https://github.com/infiniflow/ragflow/issues/8324

### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

1. rename var
2. update if statement

### Type of change

- [x] Refactoring

---------

Signed-off-by: Jin Hai <haijin.chn@gmail.com>
Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>

### What problem does this PR solve?
Feat: Add a tool operator node from the agent form #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Fix illegal variable name in Jinja2. #8316.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

Fix sandbox sandalone context error. #8307.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

Feat: Add tool nodes and tool drop-down menu #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?
Feat: Add child nodes and their connecting lines by clicking #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Fix typo in code

### Type of change

- [x] Refactoring

---------

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

### What problem does this PR solve?

- Highlight current language in README badges by changing color for
Traditional and Simplified Chinese

### Type of change

- [x] Documentation Update

### What problem does this PR solve?

- Replace hardcoded 255-byte file name length checks with
FILE_NAME_LEN_LIMIT constant
- Update error messages to show the actual limit value
- #8290

### Type of change

- [x] Refactoring

Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>

### What problem does this PR solve?

- Add validation for empty filenames in document_app.py and trim
whitespace

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

Feat: Add a child operator node by clicking the operator node anchor
point #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Add authorization header for MCP server based on [OAuth
2.1](https://datatracker.ietf.org/doc/html/draft-ietf-oauth-v2-1-12#section-5).

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Feat: Modify the anchor point positioning of the classification operator
node #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Update readme

### Type of change

- [x] Documentation Update
- [x] Refactoring

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

### What problem does this PR solve?

- Add filename length validation (<=255 bytes) for document
upload/rename in both HTTP and SDK APIs
- Update error messages for consistency
- Fix comparison operator in SDK from '>=' to '>' for filename length
check

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?
Feat: Use the node ID as the key to destroy different types of form
components to switch the form values ​​of the same type of operators
#3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Feat: Fixed the issue where the parameters could not be set after
switching the large model parameter template. #8282

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

Add documentation of authorization header for MCP server based on OAuth
2.1

### Type of change

- [x] Documentation Update

---------

Co-authored-by: writinwaters <93570324+writinwaters@users.noreply.github.com>

### What problem does this PR solve?

Add sandbox FAQ. 

#7699 #7973 #8049 #8196 #8226.

### Type of change

- [x] Documentation Update
- [x] Refactoring