Add team endpoints

[AmirAgassi]

Description

Adds new endpoints to manage team members for companies, including creating, retrieving, updating, and deleting team members

Linked Issues

• [BE Feat] Create AddTeamMember team endpoint #193
• [BE Feat] Create GetTeamMembers team endpoint #194
• [BE Feat] Create UpdateTeamMember team endpoint #195
• [BE Feat] Create DeleteTeamMember team endpoint #196
• [BE Feat] Create GetTeamMember team endpoint #197

Testing

• backend/internal/tests/team_test.go

Checklist

Before opening this PR, make sure the PR:

• Has an assignee or group of assignees.
• Has a reviewer or a group of reviewers.
• Is labelled properly.
• Has the SPUR project assigned to it.
• Has an assigned milestone.

Additionally, make sure that:

• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.
• New and existing unit tests pass locally with my changes.
• Any dependent changes have been merged and published in downstream modules.

[aidantrabs]

new common utils needs to be merged in, a lot of functions need to be updated (example: instead of doing bind and validate seperately, we have a joint helper, also error handling is different now too)