feat: improve checklist paste handling and examples

Refine logic to detect whether the current line's checklist is empty
and only strip checklist markers pasted text when the target line
is an empty checklist. When the current line contains checklist content,
convert pasted checklist lines into a new checklist item ("- [ ] ...")
instead of removing their markers. This prevents losing checklist
structure and ensures pasted content is placed appropriately.

Add numerous example builders covering:
- pasting into empty vs non-empty checklists (including blockquotes),
- multi-line paste behavior for empty and non-empty checklist targets,
- handling of non-standard checklist markers like "- [!]",
- indented empty checklist cases,
and a case that standardizes incoming non-standard markers to "- [ ]".

Update Chinese locale strings to more accurately describe the rule as
operating on task-list markers and only removing markers for empty
task-list lines.

Author: Moyf

src/lang/locale/zh-cn.ts

@@ -568,8 +568,8 @@ export default {
     },
     // prevent-double-checklist-indicator-on-paste.ts
     'prevent-double-checklist-indicator-on-paste': {
-      'name': '防止重复的清单标记',
-      'description': '粘贴时，如果光标所在行有清单标记，则从要粘贴的文本中移除清单标记',
+      'name': '防止重复的任务列表标记',
+      'description': '粘贴时，如果光标所在行有空的任务列表标记，则从要粘贴的文本中移除任务列表标记',
     },
     // prevent-double-list-item-indicator-on-paste.ts
     'prevent-double-list-item-indicator-on-paste': {

src/rules/prevent-double-checklist-indicator-on-paste.ts

@@ -31,7 +31,15 @@ export default class PreventDoubleChecklistIndicatorOnPaste extends RuleBuilder<
       return text;
     }
 
-    return text.replace(nonBlockquoteChecklistRegex, '');
+    const checklistContentMatch = options.lineContent.match(/^(\s*(>\s*)*-\s*\[.\]\s*)(.*)$/);
+    const hasContent = checklistContentMatch && checklistContentMatch[3].trim().length > 0;
+
+    if (!hasContent) {
+      return text.replace(nonBlockquoteChecklistRegex, '');
+    } else {
+      const cleanContent = text.replace(nonBlockquoteChecklistRegex, '');
+      return '\n- [ ] ' + cleanContent.trim();
+    }
   }
   get exampleBuilders(): ExampleBuilder<PreventDoubleChecklistIndicatorOnPasteOptions>[] {
     return [
@@ -64,7 +72,7 @@ export default class PreventDoubleChecklistIndicatorOnPaste extends RuleBuilder<
         },
       }),
       new ExampleBuilder({
-        description: 'Line being pasted into a blockquote with a checklist indicator has its checklist indicator removed when current line is: `> - [x] `',
+        description: 'Line being pasted into a blockquote with empty checklist has its checklist indicator removed when current line is: `> - [x] `',
         before: dedent`
           - [ ] Checklist item contents here
           More content here
@@ -79,7 +87,7 @@ export default class PreventDoubleChecklistIndicatorOnPaste extends RuleBuilder<
         },
       }),
       new ExampleBuilder({
-        description: 'Line being pasted with a checklist indicator has its checklist indicator removed when current line is: `- [ ] `',
+        description: 'Line being pasted into empty checklist has its checklist indicator removed when current line is: `- [ ] `',
         before: dedent`
           - [x] Checklist item 1
           - [ ] Checklist item 2
@@ -93,8 +101,57 @@ export default class PreventDoubleChecklistIndicatorOnPaste extends RuleBuilder<
           selectedText: '',
         },
       }),
+      new ExampleBuilder({
+        description: 'Line being pasted into non-empty checklist creates a new line when current line is: `- [ ] Existing content`',
+        before: dedent`
+          - [x] New checklist item
+        `,
+        after: dedent`
+
+          - [ ] New checklist item
+        `,
+        options: {
+          lineContent: '- [ ] Existing content',
+          selectedText: '',
+        },
+      }),
+      new ExampleBuilder({
+        description: 'Multi-line paste into empty checklist: only first line checkbox removed, rest lines unchanged when current line is: `- [ ] `',
+        before: dedent`
+          - [x] First line content
+          - [ ] Second line content
+          Regular text line
+        `,
+        after: dedent`
+          First line content
+          - [ ] Second line content
+          Regular text line
+        `,
+        options: {
+          lineContent: '- [ ] ',
+          selectedText: '',
+        },
+      }),
+      new ExampleBuilder({
+        description: 'Multi-line paste into non-empty checklist: creates new line, only first line becomes checklist when current line is: `- [ ] Existing`',
+        before: dedent`
+          - [x] First line content
+          - [ ] Second line content
+          Regular text line
+        `,
+        after: dedent`
+
+          - [ ] First line content
+          - [ ] Second line content
+          Regular text line
+        `,
+        options: {
+          lineContent: '- [ ] Existing',
+          selectedText: '',
+        },
+      }),
       new ExampleBuilder({ // accounts for https://github.com/platers/obsidian-linter/issues/748
-        description: 'Line being pasted as a checklist indicator has its checklist indicator removed when current line is: `- [!] `',
+        description: 'Line being pasted into empty checklist has its checklist indicator removed when current line is: `- [!] `',
         before: dedent`
           - [x] Checklist item 1
           - [ ] Checklist item 2
@@ -123,6 +180,33 @@ export default class PreventDoubleChecklistIndicatorOnPaste extends RuleBuilder<
           selectedText: '- [!] Some text here',
         },
       }),
+      new ExampleBuilder({
+        description: 'Non-empty checklist creates new line with standard checkbox: `- [!] Non-empty` with `- [x] Content`',
+        before: dedent`
+          - [x] Content to paste
+        `,
+        after: dedent`
+
+          - [ ] Content to paste
+        `,
+        options: {
+          lineContent: '- [!] Non-empty',
+          selectedText: '',
+        },
+      }),
+      new ExampleBuilder({
+        description: 'Handles indented empty checklist correctly: `  - [ ] ` (with 2 spaces)',
+        before: dedent`
+          - [x] Indented content
+        `,
+        after: dedent`
+          Indented content
+        `,
+        options: {
+          lineContent: '  - [ ] ',
+          selectedText: '',
+        },
+      }),
     ];
   }
   get optionBuilders(): OptionBuilderBase<PreventDoubleChecklistIndicatorOnPasteOptions>[] {