feat(Watermark): add Watermark component

[ArgoZhang]

add Watermark component

Summary of the changes (Less than 80 chars)

简单描述你更改了什么, 不超过80个字符；如果有关联 Issue 请在下方填写相关编号

Description

fixes #5098

Regression?

• Yes
• No

[If yes, specify the version the behavior has regressed from]

[是否影响老版本]

Risk

• High
• Medium
• Low

[Justify the selection above]

Verification

• Manual (required)
• Automated

Packaging changes reviewed?

• Yes
• No
• N/A

☑️ Self Check before Merge

⚠️ Please check all items below before review. ⚠️

• Doc is updated/provided or not needed
• Demo is updated/provided or not needed
• Merge the latest code from the main branch

Summary by Sourcery

Add a new Watermark component.

New Features:

• Introduce a new component for creating watermarks on content.

Tests:

• Add unit tests for the Watermark component.

[sourcery-ai]

Reviewer's Guide by Sourcery

This pull request introduces a new Watermark component. It includes a JavaScript module for dynamic watermark creation and updates, a C# component for rendering, and integration with existing components and localization.

Sequence diagram for Watermark component initialization and updates

sequenceDiagram
    participant C as Component
    participant JS as JavaScript Module
    participant Canvas as Canvas API
    C->>JS: init(id, options)
    JS->>Canvas: Create canvas element
    JS->>Canvas: Set font and context
    Canvas->>Canvas: Draw watermark text
    Canvas-->>JS: Return base64 image
    JS->>JS: Create watermark div
    JS->>JS: Setup mutation observer
    Note over JS: Monitor DOM changes
    JS-->>C: Watermark initialized
    Note over C,JS: When properties change
    C->>JS: update(id, options)
    JS->>Canvas: Recreate watermark
    Canvas-->>JS: Return new base64 image
    JS->>JS: Update watermark div

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File-Level Changes

Change	Details	Files
Added a new Watermark component.	Created the Watermark component in C# and JavaScript. Implemented dynamic watermark creation and updates. Added a sample page for demonstration. Added unit tests for the component. Integrated the component with existing localization and styling.	src/BootstrapBlazor/Components/Watermark/Watermark.razor src/BootstrapBlazor/Components/Watermark/Watermark.razor.cs src/BootstrapBlazor/Components/Watermark/Watermark.razor.js src/BootstrapBlazor/Components/Watermark/Watermark.razor.scss src/BootstrapBlazor.Server/Components/Samples/Watermarks.razor src/BootstrapBlazor.Server/Components/Samples/Watermarks.razor.cs test/UnitTest/Components/WatermarkTest.cs
Updated project files and documentation.	Added the Watermark component to the project file. Updated the documentation to include the new component. Added menu item for the new component. Added localized strings for the new component. Included the component's stylesheet in the main stylesheet.	src/BootstrapBlazor/BootstrapBlazor.csproj src/BootstrapBlazor.Server/docs.json src/BootstrapBlazor.Server/Extensions/MenusLocalizerExtensions.cs src/BootstrapBlazor.Server/Locales/en-US.json src/BootstrapBlazor.Server/Locales/zh-CN.json src/BootstrapBlazor/wwwroot/scss/components.scss

Assessment against linked issues

Issue	Objective	Addressed	Explanation
#5098	Add a Watermark component to the BootstrapBlazor library	✅
#5098	Implement configurable watermark functionality with customizable text, font size, color, rotation, and gap	✅
#5098	Provide a demo and documentation for the new Watermark component	✅

Possibly linked issues

• feat(Watermark): add Watermark component #5098: The PR implements the requested Watermark component.

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[sourcery-ai]

Hey @ArgoZhang - I've reviewed your changes and they look great!

Here's what I looked at during the review

• 🟡 General issues: 1 issue found
• 🟢 Security: all looks good
• 🟡 Testing: 1 issue found
• 🟢 Complexity: all looks good
• 🟢 Documentation: all looks good

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (0d7e077) to head (11693d4).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #5099   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files          632       633    +1     
  Lines        28105     28136   +31     
  Branches      4034      4036    +2     
=========================================
+ Hits         28105     28136   +31     

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