Update Macros documentation and External Workbenches with new addons

[hikali123456789]

Summary

This PR addresses two documentation issues by updating the Macros page and the External Workbenches page.

Issue #332: Maintaining Macros

Macros.wikitext has been significantly expanded:

1. Macro repositories section - Expanded from a brief paragraph to four detailed subsections:

   • Official FreeCAD-macros repository on GitHub
   • Macros recipes wiki page
   • Addon Manager as the easiest installation method
   • Addons index repository (Index.json)

2. New: Macro categories section - Lists all 21 categories from Macros_recipes with links:
   3D View operations, Animation, Code and scripting, Conversion, Draft Workbench and 2D, Fem Workbench, Gui, Info and measurements, Libraries, Mathematical functions, Object creation, Object transformation, Object visibility, PartDesign Workbench, Printer 3D, Raytracing, Spreadsheet Workbench, TechDraw Workbench, Utility, Wizards, Woodworking

3. New: Installing macros section - Three installation methods documented:

   • Via the Addon Manager (recommended)
   • Manual install from GitHub
   • Manual install from the wiki

Issue #331: External Add-on Documentation

External_workbenches.wikitext has been updated:

1. Removed obsolete warning - Deleted the outdated VeryImportantMessage template

2. New: Installing external workbenches section - Two methods:

   • Via the Addon Manager (with step-by-step instructions)
   • Manual installation from GitHub (with InitGui.py requirement noted)

3. New: The Addons Index section - Explains:

   • The official Addons repository and Index.json
   • Curated vs non-curated addon classification
   • Link to Addon Academy for developers

4. 8 new addon entries added to the table:

   • Assembly4.1 (community fork of Assembly4)
   • CamScripts (CAM tools)
   • Behave-Dark-Colors (dark theme)
   • Catppuccin (pastel theme)
   • Dracula (dark theme)
   • BillOfMaterials (BOM generation)
   • Alternate OpenSCAD (improved OpenSCAD import)
   • Channels (channel profiles)

5. Updated existing entries:

   • CadQuery: Updated repository URL and author info
   • CADExchanger: Reclassified to "Import and export"

[Reqrefusion]

Do not add T tags yourself; only modify the files in the wiki root directory, do not touch the translation files. Please check the latest version and ensure that the information you are adding has not been added previously. Also, be sure to cite the source of your change. Regression corrections should not be added to the documentation. And it should never contain information that the end user shouldn't know. "It's working as it should" isn't enough to be included.

[Reqrefusion]

Do not add T tags yourself; only modify the files in the wiki root directory, do not touch the translation files. Please check the latest version and ensure that the information you are adding has not been added previously. Also, be sure to cite the source of your change. Regression corrections should not be added to the documentation. And it should never contain information that the end user shouldn't know. "It's working as it should" isn't enough to be included. The reasons for each change made, along with their sources, should be explained individually.