Some rephrasing in release notes and fixes in interconnection md

## Overview

3GPP Release 16 introduced CAPIF Interconnection to enable distributed deployments and interactions between different API providers. This enhancement allowed multiple CCFs — either of the same or different trust domains — to seamlessly interact, discover services, and publish APIs with one another. At the same time, CAPIF Interconnection enables API invokers to utilize the service APIs from 3rd party API providers.

3GPP Release 16 introduced CAPIF Interconnection to enable distributed deployments of CAPIF Core Functions (CCFs) and interactions among API providers/invokers of various domains. More specifically, this enhancement allowed multiple CCFs — either of the same or different trust domains — to seamlessly interact, discover services, and publish APIs with one another. At the same time, CAPIF Interconnection enables API invokers to utilize the service APIs from 3rd party API providers.

According to the specifications, CAPIF-6 or CAPIF-6e reference points have been defined to enable communication between two CCFs. Through those interfaces CCFs can: 

### Interconnection establishment and syncronization

Interconnection establishment is initiated by the CAPIF administrator of a local CCF (CCF-A), using the "/request" API, towards a peer CCF (CCF-B).

More specifically:

POST /helper/interconnection/request with { "dstProvDom": "CCF-B host:port" }

#### **CAPIF Interconnection**

New developments perform to include new functionality for this release. Current work include:

Implementation of **CAPIF Interconnection** capability to enable multiple CCFs — either of the same or different trust domains — to seamlessly interact, discover services, and publish APIs with one another. At the same time, CAPIF Interconnection enables API invokers to utilize the service APIs from 3rd party API providers.

In order to include this functionality in the release the following developments were performed:

- Creation of new Helper API to manage CAPIF interconnection.

- Logic related with Publish at interconnection time and after interconnection implemented.

- Security Context creation now supports Interconnection, allowing OAUTH, PSK and PKI security methods.

- New way to read configutation yaml files inside microservices, allowing forwarding to local variables. This changes also HELM scripts at configuration map file.

- Creation of new Helper API to manage CAPIF interconnection establishment among CCFs.

- Publish API funcationalities (Publish, Update/Modify, Unpublish) support interconnection feature.

- Security Context API funcationalities (Create context, Get, Delete, Create Access Token) now support interconnection, allowing OAUTH, PSK and PKI security methods.

- New way to read configuration yaml files inside microservices, allowing forwarding to local variables. This changes also HELM scripts at configuration map file.

- Local scripts improved in order to allow interconnection tests with local deployments.

- NGINX image is upgraded to latest version of debian.

- All docker images are updated to python 3.13.

- New set of tests with robot framework created in order to test interconnection. Check [Interconnection Test Plan](./testing/testplan/helper/interconnection/README.md)

- New Section at documentation with detailed information of this Feature at [Interconnection section](./interconnection/interconnection.md)

- New section at documentation with detailed information of this Feature at [Interconnection section](./interconnection/interconnection.md)

#### **CAPIF Open Discover Service**