feat(analytics): make analytics optional for self-hosted installations

[rohitdash08]

#427

What kind of change does this PR introduce?

Feature - Makes analytics optional for self-hosted installations by introducing environment variable controls.

Why was this change needed?

Self-hosted users are typically more privacy-conscious and may not want analytics tracking enabled by default. Additionally, the analytics data being collected wasn't accessible to self-hosted users, making the feature unnecessary for their installations.
This change gives users more control over their privacy settings and aligns better with the expectations of self-hosted users who prefer to have explicit control over tracking and analytics.

Checklist:

Put a "X" in the boxes below to indicate you have followed the checklist;

• I have read the CONTRIBUTING guide.
• I checked that there were not similar issues or PRs already open for this.
• This PR fixes just ONE issue (do not include multiple issues or types of change in the same PR) For example, don't try and fix a UI issue and include new dependencies in the same PR.

[vercel]

@rohitdash08 is attempting to deploy a commit to the Listinai Team on Vercel.

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[nevo-david]

Hi!
There's already some checking if to start the analytics or not