[ADD] estate: Server Framework 101 implementation

[Lud0do1202]

Server Framework 101

This PR follows the official Odoo backend tutorial: 🔗 https://www.odoo.com/documentation/18.0/developer/tutorials/server_framework_101.html

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✅ Summary of features implemented:

• Create models: EstateProperty, EstatePropertyType, EstatePropertyTag, EstatePropertyOffer

• Add views: form, list, kanban, and search (with filters and groupings)

• Implement business logic:

  • Computed fields and onchange methods
  • Actions: mark as sold, cancel, accept/refuse offers
  • SQL and Python constraints (e.g. pricing, uniqueness)

• UI improvements:

  • Decorations (success, danger, etc.)
  • Smart buttons (e.g. access related offers)
  • Badges and conditional field attributes (readonly, invisible, optional)

• Seller experience:

  • Display properties by seller
  • Restrict deletion to 'new' or 'cancelled' states
  • Enforce offer price to be higher than current best

• Set default ordering on models

• Add a new module: estate_account

  • Overrides the "mark as sold" action
  • Automatically generates an invoice for the sold property

[robodoo]

[barracudapps]

@Lud0do1202 Can you also please review the name of your PR and your commits titles/messages ? Everything you need to know is here

[barracudapps]

@Lud0do1202 Goo job on commit and PR titles but you are working in the estate module. Not the real_estate one. 🙄

[barracudapps]

@Lud0do1202 Congrats for having finished the Python tutorial! 🥳 Can you please check if you considered everything I asked you to do before making Owl fly? To help you get used to Odoo's standards, please make another branch for the Owl tutorial (and a new PR too), squash your commits related to the Python tutorial here into one, rename your PR to match your commit title and add a description to your PR so your reviewer understands why you did this.